Add "is_range_interesting()" callback filter to depth_first_traversal.
Clarified comment
Typo
Converted geo index traversal to use a btree concurrent traversal
Cleaned up key variable names in geo index traversal code.
Respect interruptor in geo traversal.
Merge branch 'next' into daniel_2854
Towards lazy get_intersecting(): Brought it to a state that sort of works, except that there is no filtering of duplicates yet.
Merge branch 'next' into daniel_2854
Completed implementation of lazy get_intersecting. Testing an unit test pending.
Fixed problem with intersecting_reader_t sometimes reporting a stream as exhausted when it isn't.
Fixed bugs, refactored reader_t.
Remove debug printfs
Removed an outdated comment
Merge branch 'next' into daniel_2854

Conflicts:
	src/rdb_protocol/geo/indexing.hpp
Apply array size limit to distinct primary key set during geo traversal.
Make geo index traversal release the keyvalue pair earlier.
Clarified some comments
ReQL test to assert the result type of getIntersecting()
Added a getIntersecting cursor connection test.