Arduino Plugin for Unreal Engine 4

Originally written by Daniel Macedo, as found at https://bitbucket.org/danielvmacedo/arduinokitue4

Changes:

Code fixed to compile with Unreal Engine 4.20
Updated RS-232 code, as found at https://www.teuniz.net/RS-232/

Tested to compile for Linux UE4.20

Not tested to actually work - no Arduino board