Add search2 role

[jeanleonov]

Is required by https://github.com/AppScale/appscale/pull/3011.

[jeanleonov]

Daily build 5880 is run against:

• https://github.com/AppScale/hawkeye/pull/150
• https://github.com/AppScale/appscale-testing/pull/357
• https://github.com/AppScale/appscale-tools/pull/739
• https://github.com/AppScale/appscale/pull/3011

All these PRs should go together

[jeanleonov]

https://ocd.appscale.com:8080/job/Daily%20Build/5899/

[jeanleonov]

https://ocd.appscale.com:8080/job/Daily%20Build/5991/