Require travel plans on financial aid form

More specifically, require travel plans on the financial aid
form if and only if a travel grant is requested. Implemented
by leaving the form field technically not required, adding
form validation that looks at whether a travel grant is requested,
and marking the travel plans field with 'required' styling
manually.
More translation updates

* Django settings to tell Django what languages we're using and where
  to find our translation files.
* Mark more strings for translation.
* Update the comments at the top of locale/fr/LC_MESSAGES/django.po
* Add some doc for how to translate
* Fix use of blocktrans in some templates
* Update finaid doc while I'm here
* Ran make_messages & compile_messages to update the translation files.
Limit speaker bio field to 100 words
No markdown for speaker bio; expand help text
Merge pull request #172 from caktus/feature/translation-process-2

More translation updates
Merge pull request #171 from caktus/feature/171-limit-speaker-bios

Limit speaker bios to 100 words
Merge pull request #170 from caktus/feature/travel-plans-field

Require travel plans on financial aid form
Adding selectable support to Add Speaker form
Address some PR feedback
resolve issues with clean and selectable, add validator to prevent adding the original Speaker author as a Speaker
Mark more text for translation
Customize lookup get_query to account for looking up a portion of User.get_full_name
Merge pull request #174 from caktus/feature/translation-3

Mark more text for translation
resolve conflict from latest merge
adding i18n for template
simplifying the split
make lookup case insensitive for get_full_name comparisons
Optimize!
adding more strings for translation
adding more strings for translation