Update gRPC client doco for changed requirements.
@murgatroid99 does this read accurately? I guess what I'm unsure of here is whether grpc core is distributed as a binary by these packages, or if it is compiled from source (and a c and/or c++ compiler is required to be installed for the build). I seem to recall it needing to build from source last time I tried grpc+node on windows.
Yes, that's correct. What you're describing used to be the case, but now we publish precompiled binaries for Linux, Mac, and Windows.