Feature/straz/i18n - rake tasks to generate strings

Fix/cdodge/dangling verticals on delete

Sort the css and js assets by numerical index

undo adding .gitignore to itself

both tests work

ran tests successfully with
$cd i18n; python -m unittest test

This reverts commit acfd0d9f, reversing
changes made to e4194c99.

This reverts commit 57427f9a, reversing
changes made to 37621c26.

Master went from 5d912b88616f05c5ec10e89b336bd1088042bba0 to
e43c2bd4. 5d912b8a is a merge commit
that merged a branch onto master, so I am merging the same commit
back into master.

awareness'

Move Pearson login to external_auth

add a delete-all-versions flag to the delete_item method in the modulestores. Extend tests to verify. Still wip

* hide the login behind a setting that is turned off by default
* clean out some of the outdated settings and hardcoded test strings