Remove SPDY support from GRPC

Will re-create the E2E tests through GFE when we can properly initiate HTTP2 with GFE.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=68488736
20 files changed
tree: b14970a9a93b854711754af3bd187412797edf12
  1. core/
  2. stub/
  3. testing/
  4. LICENSE