project: Add Tagging feature.

While getting tags:
* Return 406 if the client cannot accept appcation/json.

While tagging:
* Return the tag if that is tagged newly.
* Create new tag if no tag matches the given name.
* Do nothing if that has been tagged already.

While untagging:
* Respond 404 if no tag matches the given id.
* Delete the tag if there is no project tagged by that.
Merge pull request #9 from npcode/feature/project-tag

project: Add Tagging feature.
fix author avatar CSS(34x34), project list style
Merge branch 'master' of https://github.com/nforge/hive

Conflicts:
	app/views/user/info.scala.html
ui.FindUser to ui.Typeahead for general use
enhance author avatar CSS (32x32, 64x64)
fix hive.FileDownloader instance problem
apply author avatar CSS
fix prjmenu
fix page title