Add hangout ID in addition to URL

In an effort to debug the "wild hangout URL appears" double-set
in-the-wrong-hangout errors, store the hangout ID when setting the
hangout URL.  This is just for logging presently; the ID is not used for
any other logic.
Merge branch 'master' into hangoutid

Conflicts:
	test/test.mock-hangout.selenium.js
Merge pull request #260 from drewww/hangoutid

Hangoutid