The commit message box and commit button should be disabled during a commit operation

[Xapphire13]

Description

Commit message and commit button remain enabled during the execution of a commit. This is likely not noticeable usually, but my project has a long running pre-commit hook so I have a large window to observe.

Steps to Reproduce

1. Modify a file
2. Stage it
3. Type a commit message
4. Hit commit

Expected behavior:
The "commit message" box and the commit button should become disabled until the operation completes.

Actual behavior:
Both the message box and commit button are enabled. I can click commit as many times as I wish and all but the first lead to an error message.

Versions

OS: Windows 10 x64
Atom: 1.18.0 x64
atom/github: 0.3.3

Additional Information

Successful commit, UI elements remaining enabled:

Clicking commit multiple times (ignore the output in the error, that's the preamble in my pre-commit hook):

[BinaryMuse]

I'm going to call this closed as of #1043 even though there's not a great way to disable the actual message editor box. We can tackle additional UI improvements there in the future.