New release version (google#826)

New release 20181116 (google#712)

* New release

* New release

* New release

Update setup.py

Version 20180612 (google#630)

New release 20170721

Merge pull request google#194 from google/2016.7

Release 2016.7

Merge pull request google#161 from google/160-release-2015.12

2015.12

Merge pull request google#129 from google/2015.7.3

2015.7.3 release

Merge pull request google#126 from google/2015.07.2

New release 2015.07.2

Merge pull request google#116 from google/work

Maintainance release