There is now a new option on the /status end-point. If you specify "ignore_errors=false" the the /status end-point will return an HTTP 500 error if there is a problem connecting to Cassandra or of the query index is status RED for the management app.

This change removes the HealthCheckFilter that was added last week to allow us to fail fast when there is an error connecting to Cassandra or ElasticSearch.

This change adds some new methods at the Core module level:
1) EntityManagerFactory.getEntityStoreHealth(), which returns GREEN if the Cassandra connection is OK, or RED if it is not.
2) EntityManager.getIndexHealth(), which returns GREEN, YELLOW or RED depending on the status of the EntityManager's application index.
Add new ignore_error argument to /status end-point, which defaults to true and, also added Index health check to the /org/app/status end-point.
Merge remote-tracking branch 'origin/two-dot-o' into key-row-sharding

Conflicts:
	stack/corepersistence/queryindex/src/main/java/org/apache/usergrid/persistence/index/impl/EsEntityIndexImpl.java
	stack/corepersistence/queryindex/src/test/java/org/apache/usergrid/persistence/index/impl/EntityIndexTest.java
	stack/rest/src/main/java/org/apache/usergrid/rest/filters/HealthCheckFilter.java
	stack/rest/src/main/webapp/WEB-INF/web.xml
Fixes the init calls in the rest tier and docker io issues
Changed process to use files instead of memory.  we run out of memory when running all tests in a suite.