Clarify attribute and class naming

[pnuu]

The naming of attributes and classes need clarifying.

• MoveItBase.notifier and MoveItBase.watchman handle the changes in the configuration file. This should have indication of their use
• server.reload_config() has similarly named kwargs notifier_builder=None and manager=RequestManager that are used for detecting new files. The naming should indicate this. In addition, these are never used in any of the Trollmoves scripts, so maybe the could be removed altogether?
• Both server.py and client.py implement EventHandler, only the one in server.py is used. Maybe this should be in utils.py?
• MoveItBase has an attribute self._np, which is only used by the MoveItClient class in bin/move_it_client.py, but the publisher is stopped in move_it_base.MoveItBase.chains_stop(). This should be renamed (self._noisy_publisher?) and the whole class moved to trollmoves/client.py
• MoveItServer in bin/move_it_server.py should be moved to trollmoves/server.py