CDRIVER-360 add additional geo index options

Closes #109
pulling in latest libbson
CDRIVER-453 remove replica set member limit

o Make the number of replica set member nodes dynamic.
o Fix some of the sharding and replica set tests.
o Fix a bug in socket error reporting

Closes #112
CDRIVER-446 Fix a leak in mongoc_client_command_simple()

fix a leak in mongoc_client_command_simple().

Fix some other random leaks while we're at it

Closes #110
Merge branch 'mongodb-master'

Conflicts:
	src/mongoc/mongoc-cluster.c