RUBY-256 - Execution profiles

* Updated CHANGELOG.

Author: stamhankar999

CHANGELOG.md

@@ -3,6 +3,7 @@ Features:
 * Do not mark a host as down if there are active connections.
 * Update Keyspace metadata to include collection of indexes defined in the keyspace.
 * Update Table metadata to include trigger-collection and view-collection metadata.
+* Added execution profiles to encapsulate a group of request execution options.
 
 Bug Fixes:
 * [RUBY-255](https://datastax-oss.atlassian.net/browse/RUBY-255) ControlConnection.peer_ip ignores peers that are missing critical information in system.peers.