Implement standard integration tests (almost).

Our pre-existing tests were slightly different from the integration
tests to be implemented in each language. Change our implementation to
match.

Unfortunately, the standard tests actually trigger Netty flow control
bugs, so we decrease stream sizes to <64K as a workaround.

Because the tests now compare to golden responses, they detected that
the cpp server was sending all a's instead of all 0s. That is now fixed.

We receive errors hitting CPP server for empty_unary and the various
streaming tests, so java_cpp isn't enabled in interop_scenarios.txt.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=79086882
3 files changed