Replace Google Code URLs with corresponding GitHub URLs.

GitHub pull request #1876.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=79275279
Add support for Travis CI.

GitHub pull request #1877.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=79275478