Support for process aliases and erlang:monitor/3

[mat-hek]

In short, process aliases make it possible to create a reference that can be used to send messages to a process. The important feature is that when alias is removed, the messages sent via it no longer reach the aliased process. Aliases are used by erlang:monitor/3, which creates a monitor and alias at the same time, and this is used in two important places:

• OTP's gen:call, to ignore replies after a call timeouts
• Elixir's Task.async, for Task.ignore and possibly more

Thus, for us it's quite important that AtomVM supports it. As always, happy to contribute and looking forward to your guidance ;)