Make SDLC backend configurable

[akphi]

• 1st phase: the refactoring we have to do in SDLC codebase
  • Moving Gitlab and In-Memory out to its own module
  • Create a bundle:
    • Web-filter
    • Dropwizard (module mapping, dependency injection)
  • Configuration:
    • Backend configuration
  • [ ]Think about the shaded JAR module + Docker setup
• 2nd phase: the refactoring that we need to do in tandem with Studio
  • Create set of enum of features, backend returns a set of enum values to tell what it can and cannot support
  • We have 3 levels of feature supports (the top is the most important and will override all the one below it):
    • Server: what feature the server itself allows
    • Backend: what the backend can support
    • Project (its own thing): we allow each project to configure what it can support,or this can be derived from user's permission
  • Studio askes the server: combine the configuration + backend (do the overlay), we have 2 APIs:
    • Server level
    • Project level