Making node id optional for all issue commands (except branch)

[hansfn]

Partially fixes #53.

If I get time, I'll do the same for project name.

[mglaman]

Rebased against master to fix conflicts. Making a few changes. I think it's fine to always have IssueCommandBase run initRepo instead of conditionally running it again in each command. Cleans things up a little.

[mglaman]

@hansfn want to give my changes a spin? Then we can merge and follow up with improving the Git repository detection

[hansfn]

The changes are fine - just merge them. (I see I forgot to use initRepo in Apply::initialize.)

The reason I kept initRepo in the specific command subclasses was to be able to keep one feature of the link command - it worked without a local repo. I don't mind loosing that feature. (I have defined search engines in Chrome with keyword "don" - drupal.ord/node/%s - so I just type "don NID" in the address, anyway.)

[mglaman]

Ah, yeah I didn't think about that for link. I'll just merge and open a follow up issue.