Update README.rst with badges for version and license (datastax#1210)

Author: bschoening

README.rst

@@ -1,3 +1,6 @@
+[![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://opensource.org/licenses/Apache-2.0)
+[![PyPI version](https://badge.fury.io/py/scylla-driver.svg)](https://badge.fury.io/py/scylla-driver)
+
 Scylla Python Driver
 ====================