Log Message:
Update databases/mongo-c-driver to 1.1.7.

mongo-c-driver 1.1.7

- Thread-safe use of Cyrus SASL library.
- Experimental support for building with CMake and SASL.
- Faster reconnection to replica set with some hosts down.
- Crash iterating a cursor after reconnecting to a replica set.
- Unchecked errors decoding invalid UTF-8 in MongoDB URIs.
- Fix error reporting from mongoc_client_get_database_names.

mongo-c-driver 1.1.6

- mongoc_bulk_operation_execute now coalesces consecutive update operations
  into a single message to a MongoDB 2.6+ server, yielding huge performance
  gains. Same for remove operations. (Inserts were always coalesced.)
- Large numbers of insert operations are now properly batched according
  to number of documents and total data size.
- GSSAPI / Kerberos auth now works.
- The driver no longer tries three times in vain to reconnect to a primary,
  so socketTimeoutMS and connectTimeoutMS now behave closer to what you
  expect for replica sets with down members. A full fix awaits 1.2.0.
- mongoc_matcher_t now supports basic subdocument and array matching

mongo-c-driver 1.1.5

- The fsync and j write concern flags now imply acknowledged writes
- Prevent using fsync or j with conflicting w=0 write concern
- Obey socket timeout consistently in TLS/SSL mode
- Return an error promptly after a network hangup in TLS mode
- Prevent crash using SSL in FIPS mode
- Always return NULL from mongoc_database_get_collection_names on error
- Fix version check for GCC 5 and future versions of Clang
- Fix warnings and errors building on various platforms
- Add configure flag to enable/disable shared memory performance counters
- Minor docs improvements and fix links from C Driver docs to Libbson docs