Remove debugging 'always open dialog'

Obviously the FIXME didn't work :(
Extend underscore with inGroupsOf function

à la Rails' in_groups_of helper method.  Is useful for splitting an
array's elements evenly into X arrays and populating a table.
Create JS version of lib/dc/languages.
Lang selection sheet use list from dc.languages
Data for model's language mixin from dc.languages
Modify views to read data from dc.languages
Language selection td may be blank

inGroupsOf pads last row to make counts work out.  The earlier
hard-coded list cheated by making rows match up.
Modify server-side to match our testing languages
save and export language on accounts
Use jquery to set current language for upload
Set language the same as other attributes

Also catches some corner cases were the language edit sheet did not get
hidden if there were no changes.