[travis] force protobuf 3.0.0b2 for Python 3
authorJonathan L Long <jonlong@cs.berkeley.edu>
Fri, 4 Mar 2016 20:53:49 +0000 (12:53 -0800)
committerJonathan L Long <jonlong@cs.berkeley.edu>
Fri, 4 Mar 2016 20:53:49 +0000 (12:53 -0800)
commitebfa2af1ca80cd7e0f23d92fca1a491b86605686
treefbef193559ee6045c992c981297aff6ee44941f3
parentc2354b98609916dd9176fbacde4e93184a6996d0
[travis] force protobuf 3.0.0b2 for Python 3

This is temporary measure to avoid an apparent upstream issue with
protobuf 3.0.0b2.post1.
scripts/travis/travis_install.sh