Implement GlobalCache emulation

[bengtmartensson]

No need for a complete implementation, just the main, IR-related commands of GC-100/Flex.

Commands:

• getdevices (just return something trivial that later the sendir command accepts, like a Flex with one transmitter)
• getversion
• get_NET (?)
• blink(?)
• sendir

Everything single threaded: accept command, process, print output. (stopir is thus not to be implemented.) Only one connection at a time. Should return compatible error codes.

Can use LEDs to indicate state (listening, sending,...).

Probably should incorporate the Beacon.

In the Arduino package, can be an "Example" parallel with Girs.[ino|cpp].

Write as much as possible stream-based, but no need (at least initially) to support anything but TCP-server mode (just like the GC devices).

First version only support one sender, no receivers/captures. Several sender, learning (get_IRL) can be implemented in a second phase.

[bengtmartensson]

Replaced by the independent project GlobalCovfefe.