Merge pull request #27 from aschrijver/master

Removed hardcoded value SAFE for write-concern.
Add back dropCollection to the Persistor.

Add documentation for count, getCollections, DropCollection, and CollectionStats.

Fixed a couple of typos.

Added tests for drop collections combined with getCollections, and also a test for CollectionStats
Comment assert check which fails on CI, because of their setup
Fix up test to work on CI test setup
Add better test that also works on CI
[#30] Send back response on MongoException
adds support for connecting to replset
update readme
Merge pull request #31 from RichardWarburton/master

Adds Support for Replica Set and Sharded Clusters
Allow cursor timeout to be specified
Disallow a negative cursor timeout