update changelog && version bump up (#116)

Author: NRHelmi

CHANGELOG.md

@@ -1,5 +1,12 @@
 # Changelog
 
+## v0.6.9
+
+* Added `poll_with_specified_overhead`
+* Added `create_engine_wait`
+* OAuth access token caching on disk `~/.rai/tokens.js`
+* Access key authentication support dropped
+
 ## v0.6.8
 
 * Added protobuf metadata support

railib/__init__.py

@@ -12,5 +12,5 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-__version_info__ = (0, 6, 8)
+__version_info__ = (0, 6, 9)
 __version__ = ".".join(map(str, __version_info__))