Setup OSS Fuzz integration (#57)
Setup OSS Fuzz integration (#57)

`.bazelrc` is copied from bazel rules_fuzzing: https://github.com/bazelbuild/rules_fuzzing/blob/f6062a88d83463e2900e47bc218547ba046dad44/.bazelrc

This gives us full OSS fuzz integration across multiple fuzzers.
grpc-ecosystem/grpc-httpjson-transcoding,grpc-ecosystem/grpc-httpjson-transcoding