.site is now a special symbol in sx-assoc-let

sx-question.el no longer manually inserts the `site` property on fetched
questions. This was insufficient because we also need this property on
other objects.
Implement voting
Move browse-filter to sx
Finish voting implementation on the question list.
sx can also updates question-mode buffer.
Add some comment filters
Fix voting for comments.
Binds for voting.
Add elements to auth-filter-auth and browse-filter
Fix wrong function
Moved interaction functions to their own file
Cleanup old obsolete line.
Question/answer score is displayed in the question buffer
Merge pull request #93 from vermiculus/voting

Voting