Set version to 2.0.1-SNAPSHOT

Change-Id: I4de1c7c52354ed100d05599371c0488f8038bd90
Reviewed-on: http://review.couchbase.org/42075
Tested-by: Michael Nitschinger <michael.nitschinger@couchbase.com>
Reviewed-by: Simon Baslé <simon.basle@gmail.com>
Reviewed-by: Michael Nitschinger <michael.nitschinger@couchbase.com>