Refactor to simplify __check_if_ready_to_run.
Move checks for in memory managed jobs prior to common path through code into their own helper method.
Refactor __check_if_ready_to_run - less code duplication...
... in the sense that it is no longer repeatedly grabbing same values from map, from wrapper, etc.
Break up __check_job_state - extract new __verify_job_ready method.
Allow dynamic job destinations to throw new JobNotReadyException to indicate delayed decision.
Perhaps wait on some deployer defined limit or resource to become available, etc...
Missed committing a new __init__.py file for Tool Shed dependencies.
Docfix: Delete diminutive docker doc deficiency.
Merged in jmchilton/galaxy-central-fork-1 (pull request #411)

Allow dynamic job destinations rules to throw `galaxy.jobs.mapper.JobNotReadyException` indicating job not ready.