Use shared methods to connect to beanstalkd

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>
Rename teuthology.queue to teuthology.worker

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>
Submit queued jobs to paddles

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>
When deleting jobs, also delete them from paddles

Signed-off-by: Zack Cerza <zack.cerza@inktank.com>