Allow cross district move keeping the same uid

  Delete move/pre-move/post-move hooks, these hooks are no longer needed.
  Remove move/pre-move/post-move hook references
  Mcollective cleanup: remove methods and references related to move, pre-move and post-move.
  Gear Move changes: Keep same uid for the gear When changing the gear from one district to another.
  Added district test case: Tests reverse_uid with preferred uid logic
  Bug fixes