Remove `Job` class, merge the important bits of it straight to `Task`
Move Tee class to utils
Refactor task queue and execution to be in manager
Strip down scheduler to just queue executions
Fix some references to removed scheduler.execute
Move task execution to own thread to handle signals/ctrl-c gracefully
Move BufferQueue to tools
Fix ipc checking for tasks already in the queue.
Move scheduler starting back to webui code.
Merge pull request #309 from Flexget/manager_refactor2

Move task execution out of scheduler