/tags/tag-name/media/recent supports Count param

Other that MinID and MaxID options, the Count param was not included in
the current implementation. This works now, and returns the exact
number of []Media when opt.Count is included in the request.
Merge pull request #1 from wari/add_count_to_tags_recent_media

/tags/tag-name/media/recent supports Count param, permitting media count to be populated if requested