Enable read-write operations on federated filesystem

- Depends on fix for MODE-2252 (https://github.com/escowles/modeshape/tree/mode-2252)
- Remove IT from connector project (because REST API transaction context is required for the tests)
- Re-enabled the REST API federation write tests
- Disable caching of generated properties

Resolves: https://www.pivotaltracker.com/story/show/70954532