Change prune_aspect_ids to aspects_from_ids, seperate out non-backgroundable piece of posting from dispatch_post

Merge branch '619-gender-aware-translations' of https://github.com/siefca/diaspora into siefca-619-gender-aware-translations

Merge branch 'cuke-features' of https://github.com/sentientwaffle/diaspora into sentientwaffle-cuke-features

- New module I18n::Backend::Genderize keeps configuration and adds :gender option to translate().
- Module methods in Genderize allow fast checking if language needs gender and guessing gender.
- jQuery in views/users/edit.html.haml shows and hides grammatical gender select list when needed.
- Span and select list in views/users/edit.html.haml allows to choose grammatical gender.
- Key :grammatical_gender in User model keeps grammatical gender information.
- Added some methods to language_helper.rb.
- UsersController is aware of grammatical gender and is able to guess it when "getting started".

This change allows users to "unset" their birthday.

Previously the logic checked to see if all values for birthday were
present (year, month, day). If all values were present the update
would proceed.

Now, there is another condition. If all values are empty, then
also proceed with the update. Thus, allowing a user to "unset" their
birthday.