adds a CleverDistrict test for limits (for uniformity)
adds events as property of other endpoints, adds events tests

The new tests are required because CleverApiResource::classUrl() adds a
prefix "push" to the ->instanceUrl() call used in the tests.
simplifies tests for adding events as second level endopint to other
endpoints
Merge pull request #8 from henderjon/master

Applied fixes based on comments from the OTHER pull request.