Always use new entity endpoints in tools and docs

[DaoWen]

#582 deprecates the /rawscheduler endpoint in favor of new entity endpoints. We should be using /jobs, /instances and /groups consistently in all of our tools (CLI, simulator, etc) and all of our documentation. The only place the old endpoints should show up in a git grep would be:

1. The endpoint implementation in api.clj
2. Integration tests that ensure the deprecated endpoints still work. These tests should be clearly marked as testing the deprecated API. I think it might be a good idea to actually move these into a separate test suite in test_deprecated.py.