This commit refactorss the check_pool method in pool_manager.
Specifically, each commented section describing a stage of check_pool is
broken out into a separate method and check_pool is simplified by
calling these methods. Without this change it is difficult to follow the
intent for or make changes to check_pool.
Additionally, a docker-compose file is added to make it simple to launch
an all-in-one vmpooler instance along with a separate redis server with
docker.
This commit updates destroy_vm to remove the redis member from the completed queue only after a destroy has been completed. Without this change a VM that is being destroyed will be logged as discovered when inventory is checked since it has already been removed from the completed queue.
This commit updates destroy_vm to remove references to its mutex tracking object when destroyed. Without this change a VM that is destroyed will leave its mutex tracking object forever causing the pool manager memory footprint to increase.
This commit adds a changelog and contributing guidelines to vmpooler. Without this change vmpooler offers no specific contributing guidelines or changelog.
