As discovered in MAGNOLIA-9184, we need access to the RepositoryContext in order to register Jackrabbit's default MBeans with the MBean server.

Implementation notes

There's currently two proposals on how this could be implemented, both with their own pros and cons:

1. PR1 specializes ProviderImpl into one that uses a different mechanism to get the repository, which provides access to the RepositoryContext.
2. PR2 factors repository creation out into a RepositoryFactory, which provide the backward compatible implementation registering the repository with JNDI and the new one only providing access to the RepositoryContext.

1. is less risky as it does not touch the existing design and implementation much but it introduces some technical debt as we need to copy and slightly change a few classes from Jackrabbit (BindableMgnlRepository, BindableRepositoryFactory, RegistryHelper).

2. is more risky and reveals some tests that need fixing. There is a potential ripple effect of this causing similar test failures in other modules. Conceptually the approach is cleaner and introduces less technical debt.