jQuery-ui 1.9.2 added
I tried adding jQuery-ui 1.9.0 but 'DatePicker' widget doesn't work.  So
that I decieded to include this newer version.
New date placeholder entry added in order to ease future changes
Trello#61 Datepicker added for it to prevent from entering an
absurd deadline date.
In fact, the deadline showed in the capture, is a valid date but it doesn't
make sense because deadline date should be a future's one.
Trello#70 - refactor assignment_generic_file (WiP)
There are some pages which still address previous routes to
assignment_generic_files.  I've fixed just one route in order to fix
Trello#61.
Production optimization added
Merge pull request #28 from fiuba/preventing_from_entering_invalid_date

Preventing from entering invalid date