Add basic OAuth support to gRPC.

The primary functionality is an interceptor that authenticates calls using oauth. However, most of the changes are for an integration test to make sure the code works with ESF.

This is based on work by lryan and simonma.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72567773
6 files changed
tree: 71a8719613733eb5fc585612c6dd2f2834f36e14
  1. core/
  2. stub/
  3. testing/
  4. LICENSE