Maintaining consistent release version

[wangchen615]

The load-watcher can either be used as a microservice and as a library.

• We need to maintain release versions so Trimaran scheduler plugins can always work with a stable release version where others can continue to contribute to other branches.
• Besides, it will make sure a specific version of Trimaran plugins work with the same release version of docker image and library regardless of whether running in client mode or in package mode.
• Need an official docker hub account for the image.