API update
Merge pull request #81 from ikhudoshyn/api-update

API update
Add consistency processing on writes to cassandra

Fixes bug 1271207
Merge pull request #85 from ikhudoshyn/bug/1271207

Add consistency processing on writes to cassandra
Merge branch 'master' of https://github.com/Mirantis/magnetodb

Conflicts:
	magnetodb/storage/impl/cassandra_impl.py