Setup i18n support

I added fabric commands to simplify the task of running the Django
admin commands to generate strings files and compile them. These require
that GNU gettext is installed.

I gitignored .mo files because they are generated by the messages
compiler.

I followed the guide https://docs.djangoproject.com/en/1.0/topics/i18n/
to set up the javascript gettext support.

The messages file for treemap was generated by the fab task and is
picking up all the gettext calls from the registration templates.
Add translation tags to existing templates

I skipped over the instance page at /{instance_id} since it has
no real content.
Add i18n to ecobenfit labels and search counts
Merge pull request #138 from jwalgran/topic/bootstrap-i18n

Bootstrap i18n