PyMongo 2.6 compatibility: override Monitor.start_sync.
Style.
Very silly style fixes.
Prohibit start/end/in_request at the MotorPool level.
Start reimplementing MotorPool: simpler, no requests, no inheritance.
Fix and refactor MotorGridFS.put().

w=0 check was completely wrong.
Slight MotorGridFS test refactoring.
Formatting.
Better means of using __simple_command in Motor.
Rearrange copy_database.