Add the ability to lock assets.

Test for locking of assets.

Merge conflict.

Add class to the tr for locked.

Hook up locking/unlocking to contentstore.

Get locking correct for new files.

Incorporate Frances' UX changes.

Merge with master.

updating locked style on studio assets page

Integration test for locking.

Get not yet implemented.

small visual cleanup on progress bar and i18n table headers on studio assets