Add Filter For Issues/Policies/Actions

[udemi]

For issues, policies, action we need a filter with the following categories:

• Best rated (most total upvotes)
• Worst rated (most total downvotes)
• Most comments (if possible)
• Most views (if possible)

We do not need the cool Reddit style filtering for the MVP, we can add that later :)

[Enrico Piccini]

Right now we've only a sorty_by ratio filter