software/ors-amarisoft: Start to organize Radio Unit related bits under ru/
Bring more structure to RU-specific code as a preparatory step for multiRU support:
- move RU-specific files under 
ru/<RU-type>/. This mostly moves Lopcomm programs and configuration files there. - move RU-specific instance code there as well. This also mostly moves Lopcomm specific services and promises there.
 - bring more structure in naming. As buildout has global namespace use 
ru_<RU-type>_prefix to avoid collision in names. 
This should be a preparatory patch with practically no semantic change, but preparing ground for further multiRU landing.
/cc @jhuge, @lu.xu, @xavier_thompson, @Daetalus