Add `QUIET` as a logging level to the python logger.
Replace `logging.getLogger()` with `logging.root` since it's the same.
Add `Queue` or `queue` for python 3 to salt's compat module.
Renamed `QueueLoggingHandler` to `TemporaryLoggingHandler`.

Renamed `salt.log.handler.QueueLoggingHandler` to a name which better defines what it does, `salt.log.handlers.TemporaryLoggingHandler`.
Added `salt.log.handlers.QueueDispatchingHandler`.

The `QueueDispatchingHandler` is a null logging handler which receives the log records and, on a dedicated thread, dispatches those same log records to all of it's provided logging handlers. This is specifically needed for slow logging handlers such as a network logging handler which might need to do some DNS queries, HTTP handlers, any logging handler that can slow down salt's processing.
All logging handlers loaded on the salt's loader system will be added to a common `QueueDispatchingHandler` and won't be added to the python's logging root logger since we can't know if the user does not use a slow logging handler which will slow down salt, and that should not happen.
Since salt now uses a queue dispatcher, there's no need to advise users to use raven's threaded transport.