feat(examples): add remote link example

[Avi-D-coder]

This example shows remote linking. It's currently broken, I believe there is a bug in remote_link, see the comments.

To run this example you need two terminals. The first run will start the supervisor, listen for connections, and run an actor foo. cargo run --features=remote --example=remote_link foo The second run will run an actor bar. cargo run --features=remote --example=remote_link bar

Note that wherever I place link_remote it returns an error to the caller, if the link is between the two processes. In other words "foo" works can be linked because it's local, but trying to link bar will cause an error. If I place the call to link_remote in main the second process will panic, and the supervisor running in the first process will report a dial error on linked actor bar.

If I place the link in the LinkMe message handler the first process will panic.