Merge branch 'master' of git://github.com/zts/Gitalist

* 'master' of git://github.com/zts/Gitalist:
  Added the search_help action.
  Don't bother looking up type - the subclasses know what they are.
  Fix commit action.
  Move diff method onto Commit object, and tree attribute into a role.
  Add ::Tag and ::Tree.
  Add ::Object::Blob.
  Moved additional attributes to :Commit.
  Introduce ::Object::Commit.