Fix `compile-proto-file` on OS X (#90)
Fix `compile-proto-file` on OS X (#90)

Before this change, `compile-proto-file` fails due to a missing `grpc` library.
After this change `compile-proto-file` runs successfully on OS X
awakenetworks/gRPC-haskell,awakenetworks/gRPC-haskell,awakenetworks/gRPC-haskell