tonic’s Hello World Example

This is the example from hyperium/tonic:examples/src/helloworld

To run, in two separate terminals, do:

cargo run \
  --bin 'server' \
  -- \
  --address '[::1]:50061'

and

cargo run \
  --bin 'client' \
  -- \
  --server_address 'http://[::1]:50051' \
  --name "World"