Categories and Collaboration proposals to blogs

[jukka]

(story #260) I understand that Collaboration proposals are for inviting people to join the group, right?

• Make groupblog to have a list of possible categories for posts.
• Make every post to have a category. Default category is 'Blog post', but another category that every group has is 'Collaboration proposal'.
• Make Collaboration proposals from all groups visible in Community front page despite the member not being a member of that group.
• Don't show Collaboration proposals older than month. (or how do we deal with them accumulating?)

[jukka]

(In [390]) Refs #438, spent 3h, remaining 1h. Categories exist now, and Community-folder collects a list of UID:s to message objects that are Colloboration proposals. Remaining to do: displaying that list.

[jukka]

(In [410]) Closed #438, spent 7h more. Had to refactor lists for recent posts and collaboration proposals. Testing also took time.