Support bazel BUILD #9

I believe bazel should be faster in CI as it greatly caches everything

• Define D rules (Add first bazel rules and BUILD. #10)
• Define DUB third-party deps BUILD (dplug and mir-core) Add BUILD defs for kdr core modules and third-party libs #11
• Support testing
• Support VST2
• Support VST3
• Support AU

Resources:

• https://levelup.gitconnected.com/continuous-deploys-with-bazel-github-actions-c508676678e8
• https://dev.to/davidb31/experimentations-on-bazel-github-action-5639
• https://github.com/AuburnSounds/Dplug/blob/4e631d5b166d623e09e411c9edd437117c32ebd8/tools/dplug-build/source/main.d#L436