This enables us to get around any CORS issues with the podcast RSS feed.
We just re-serve it from our server with CORS already enabled.

By parsing the RSS serverside and serving it up as plain json, we
no longer have to include a costly XML parsing step on the client. #80

There is now the option to point shortcut's client and server to an RSS
feed URL instead of maintaining an `episodes.json` file with manual
metadata. The admin sets the `useRSS` option in
client/src/config/default.js to `true` and provides a feed URL in the
server's .env file `RSS_FEED`.

At every point in the code where `episodes.json` might be accessed for
metadata about all episodes, the code now branches if RSS is enabled and
instead parses the RSS feed.

This closes #82.

There is now an admin panel that can be reached at the `/#/admin` route.
The panel shows a list of episodes that Shortcut knows about, as well as
their state as enabled or disabled (disabled by default). This state is
stored in `server/adminData.json` on the server.

This closes #81, because we no longer need a specific user-defined GUID
to say "episode 3098281ABD23 is enabled" -- now we use the `guid` tag
defined in the rss spec.

Fixes the following warning reported:

  npm WARN [email protected] No repository field.

Whilst Yeoman may have been used during initial, one-off generation of
the project it is unlikelt to be re-run. Remove the configuration file
from upstream repository.

Unlikely to be run again as: (1) yeoman itself isn't a dependency of this
project, and (2) low likelihood of re-running a project generator after
v1.0.0 has been released without a major refactor.

Use new abstracted name in client/ documentation.

Update documentation and example commands in server/ to reflect
new project name.

Documentation and package.json provide guidance to using nodemon to ease
the development process. However, it was missing from devDependencies in
server/package.json and a manual install instruction in server/README.md

As npm has functionality to reflect dependencies that should not be run in
--production (or when the NODE_ENV environment variable is set to production)
then let's utilize that.

This reduces the number of manual commands that must be run to setup the
recommended shortcut development environment.

Rename the existing test to *Test.js, so that shortcut-client's test runner automatically
finds the existing test for ClippingContainerComponent.

This improves code coverage as measured by lines to 25.57% (from 23.56%). See below:

 BEFORE
 --------------------------------|----------|----------|----------|----------|----------------|
 File                            |  % Stmts | % Branch |  % Funcs |  % Lines |Uncovered Lines |
 --------------------------------|----------|----------|----------|----------|----------------|
 ...
  src/components/                |    45.99 |    34.85 |    65.77 |    27.17 |                |
   ClippingContainerComponent.js |    45.96 |    25.62 |    74.19 |    22.43 |... 441,442,444 |
 ...
 --------------------------------|----------|----------|----------|----------|----------------|
 All files                       |    42.71 |    35.54 |    62.18 |    23.56 |                |
 --------------------------------|----------|----------|----------|----------|----------------|

 AFTER
 --------------------------------|----------|----------|----------|----------|----------------|
 File                            |  % Stmts | % Branch |  % Funcs |  % Lines |Uncovered Lines |
 --------------------------------|----------|----------|----------|----------|----------------|
 ...
  src/components/                |       48 |    37.02 |    66.15 |    29.78 |                |
   ClippingContainerComponent.js |    63.35 |    41.32 |    77.42 |    45.79 |... 441,442,444 |
 ...
 --------------------------------|----------|----------|----------|----------|----------------|
 All files                       |    44.25 |    37.16 |    62.95 |    25.57 |                |
 --------------------------------|----------|----------|----------|----------|----------------|

Without this peer dependency of [email protected], the following error
message is reported when running `npm install`:

  [email protected] /home/rhyskidd/Coding/shortcut/client
  └── UNMET PEER DEPENDENCY flexboxgrid@^6.3.0

  npm WARN [email protected] requires a peer of flexboxgrid@^6.3.0 but none was installed.

Reported with:
  $ npm --version
  3.5.2
  $ nodejs --version
  v6.11.4

For more on peer dependencies, see: https://stackoverflow.com/a/22004559/4206728

If no RSS_FEED is specified on the server, the `rss/` endpoint
immediately returns a 404 instead of attempting a GET request. Relevant
to #95.

Fixes a bug where two cache objects were created; we now create a single
cache object on server init, and then pass it into
`routes/all-episode-data.js`.

Forcing the entire cache to update every time, since this is only ever
called during occasional admin-only tasks. (all `cache.save()` calls
are now passed `true`);

Also updates the Admin panel to grab the full list of episodes
completely unfiltered from the server (via a call to
`/recent?filter=0`). Before this commit, disabling an episode from
appearing on the front page would also disable it from appearing in the
admin panel! (The unfiltered endpoint doesn't need to be secure since
it's pulling from the canonical rss anyway.)

This commit makes the admin panel control what appears on the front page
even if Shortcut is set up to use `episodes.json` as its metadata source
instead of RSS.

* Explicitly declare Node.js compatibility in the package.json
* Replace a console.log with a thrown Error object
* Safety-check the parent object of a subobject before testing if the
subobject exists

From @therewasaguy's PR feedback.

Infinite scroll is overengineering for this particular UX element. Even
the weakest smartphones can render ~1000 plaintext divs no problem, and
while getting all the way down to the bottom might be a problem, as long
as we don't provide a search feature (which is forthcoming) at least
rendering all the episodes on one landing page lets a user ctrl+F or
"find in page" on mobile to find the particular episode they are looking
for. Even pagination (the usual alternative to infinite scroll) would
make this impossible.

This commit makes it so we render a blank page on the Admin page until
the user successfully authenticates. Previously we rendered an empty
Admin panel but probably best to obfuscate all Admin functions prior
rendering instead of giving an empty placeholder admin panel.

(Per @therewasaguy's suggestion)

Per @therewasaguy's
[review](#96 (comment))
the '/rss' and '/recent' endpoints return the same thing if you're set
to RSS mode. So no reason to have a dedicated '/rss' endpoint, and also
no more need for a `useRSS` configuration variable on the client.

The client just asks the server for recent episodes, and the server
knows if it needs to retrieve those from the RSS feed or from the JSON
file.

Cleaned up some jshint warnings and updated moment which was throwing a
bad warning.

The all-episode-data route used to have some gnarly logic built in but I
removed that a while back. However, some confusing comments stayed in,
and also some application logic that we didn't need was in there too.
This commit removes those.

Accessing the admin panel will update the cache locally. It's just a
GET request to the RSS feed (in the case of RSS), which we wouldn't want
a normal user to intialize but is fine if an admin does it. The server
endpoint is behind an auth gate so only an admin will ever kick it off.