Initial commit to make reads work with an iterator style read

USERGRID-1161
USERGRID-1390
Conflicts:
	core/src/main/java/org/usergrid/persistence/cassandra/CassandraService.java
Cleaned up existing operations before updating the merge operations.

USERGRID-1046
Conflicts:
	core/src/main/java/org/usergrid/persistence/cassandra/CassandraService.java
	core/src/test/java/org/usergrid/persistence/CollectionTest.java
Updated geo query to load large result sets before merging.
temp commit, overwrite before push
Initial pass at iterator construction.  Need to test cursor bytes.
Intermediate commit.  Need to merge master

USERGRID-1391
Merge branch 'master' into USERGRID-1046-query-iterators
Completed refactor of iterator interface to support paging.

Completed intersection impl

Added tests for large intersection sizes.

USERGRID-1046
Finished Union

Finished Subtraction

Need to add sorting to result sets.

USERGRID-1046
Fixed bug in UNION logic

Sort order is now applied as the first scan range for intersection with
the smallest result set.
Updates ordering and cursors to work correctly

NOT intersection fails due to slicing issues

Need to update to treat id iteration the same as any other slice in
query visitor, not a special case

USERGRID-1046
Removed edge case logic for reading via ID.  This now occurs directly in
the AllNode for all queries.  The QueryProcessor handles creating this
node if no criteria or sorts are specified.

USERGRID-1046
Fixed paging with all node and slices.

USERGRID-1046
Wrapped existing GEO index search with iterators.  Need to update the
geo library to support paging.

USERGRID-1046
Fixed cleanup tools to use new id iterator
Updated geo library to support paging.

USERGRID-1046
Changed go to reduce duplicate code.  the Geocell library needs more
work before we can support paging properly.

USERGRID-1046
Updated slices and nodes to encapsulate cursors a bit better.

Updated geo logic to support paging better.

USERGRID-1046
temp commit. overwrite
Last commit before creating more tests.  

USERGRID-1046