Validate date/time settings when typed in directly.

The changeTime event isn't fired when the user types in the field, but
only when clicking on the time in the dropdown. I'd consider this a
timepicker bug, but for now we can just listen to the user typing in
the field and update the value (and thus validate) like we do with
other field types.
Adds integration tests for word_cloud module
CMS i18n changes from Tsinghua
change from_xml class method on video class to make sure we honor the fact that the xml string could actually be a pointer to another file on disk which actually contains the attributes
add back removed space
Fixes for `vagrant up`

vagrant:
  - check actual IP;
  - only init machine first time, just as native installations;
  - add .bash_profile to permissions fixup;
  - cleanup excessive newlines in making .bash_profile;

README:
  - include admin & debugging use;
  - info about re-initializing VM & manually running create-dev-env.sh;
  - add django admin & debug_toolbar setting info

Conflicts:
	AUTHORS
	scripts/vagrant-provisioning.sh
Studio: adds a space back to the phrase 'Welcome to edX Studio' that went missing
Studio: revises spacing fix for welcome to edX studio title
Merge pull request #443 from edx/tsinghuax/cms-i18n-leftovers

CMS i18n changes from Tsinghua
Use Backbone notifications for course section delete.
Use Backbone notifications for component delete.
Use Backbone notifications for setting graded status.
Factor out common code between module editing and course overview.
Studio: changed the copy and prompt type for unit + outline deletions
Remove `@xhr.restore()` to fix tests.
Merge pull request #403 from edx/peter-fogg/fix-stud-421

Validate date/time settings when typed in directly.
Add endpoints to set user notification preference

Two endpoints are intended to be used by AJAX calls from the web UI with an
authenticated user. When enabled, the value of the preference is an encryption
of the username, to be used as a token for one-click unsubscribe links. The
third endpoint is the target of unsubscribe links, which displays a page with
an appropriate message to the user.
Add acceptance test for one-click unsubscribe page
Merge pull request #453 from edx/yarko/vagrant-up-fix

Fixes for `vagrant up`
Remove commented-out code and add test.