Add README with description, license undecided, dev instructions
Show current branch (hardcoded to master) and sha (polled from back-end)

All the logic is in the controller; I'll eventually pull it out into an
angular Service or something.

I thought about putting the `$timeout(updateSha, 1000)` inside the
`finally` part of a `try...finally`, but there isn't actually much
that can go wrong; if `data` doesn't have a `sha` attribute then
`data.sha` is `undefined`, not an exception as in other languages.
Test that test-pack branch sha is displayed

This is an end-to-end test for the functionality added in the previous
commit.

You have to manually start the backend before you run the test with
`npm run protractor`. It will automatically launch an instance of
Chromium and control it via WebDriver.

Protractor is the end-to-end test runner installed by angular-seed,
and it's the test runner recommended in the Angular tutorial.[1]

If we need more flexibility in future[2] we might consider writing tests
in python using the Selenium (WebDriver) python bindings. I'm also
committing "notes.md" with what I've figured out so far to do that.
But at least this is testing the real javascript code in a real browser
against the real back-end service.

[1] https://docs.angularjs.org/tutorial/step_03#running-end-to-end-tests-with-protractor

[2] For example, test that the sha is updated in the Web UI when you
    push a new commit to the git repo -- that's not something I intend
    to script from the javascript test code.
Use $interval, not $timeout, to poll backend

To allow end-to-end testing with Protractor. See "Waiting for Page
Synchronization" at
https://github.com/angular/protractor/blob/fcd973b/docs/timeouts.md