Review es6 template files and simLauncher.js

[Denz1994]

Related to #872, for reviewing sim-webpack.ejs, sim-development.html, and SimLauncher.js:

sim-webpack.js

• Some top-level documentation indicating the file's use would be useful. I only see this file being used as a template for starting a webpack dev server (`webpackDevServer.js)

simLauncher.js

• The dynamic imports in initializeDynamicImports assumes the path is correct. Perhaps a catch block would be useful for logging an error message for an incorrect path.
• pendingLocks type doc is missing. {Array.<Lock>}?
• launchBegan and launchComplete are missing type docs. {Boolean}?
• launch() and proceedIfReady() aren't using ES6 arrow functions
• proceedIfReady() missing jsDocs
• createLock(object) parameter isn't described in the jsDoc. @param {Object} object?

sim-development.html
Nothing to note for this file.

Assigning to @jonathanolson to respond to the above points.

[jonathanolson]

Looks like some other cleanup was done, but I believe I fixed up all but one thing.

The dynamic imports in initializeDynamicImports assumes the path is correct. Perhaps a catch block would be useful for logging an error message for an incorrect path.

I wasn't involved with the dynamic import setup for this. The try-catch wouldn't work with the promises, but we could use .catch() or .finally(). @samreid thoughts?

[samreid]

If an incorrect path is provided, the browser will show an error like:

simLauncher.js:21 GET http://localhost/main/brxand/phet/js/Brand.js net::ERR_ABORTED 404 (Not Found)

Is that sufficient?

[Denz1994]

Thanks for checking @samreid. I wasn't sure how exactly this would fail (hopefully not silently) but the error message shown looks clear. I'll close this issue because the items have been addressed.