implement RLM SML

[ffaerber]

this SML should work https://github.com/buzzn/d0-reader/blob/master/sml_info/rlm.sml

[drthth]

Hi @ffaerber , the recommended library for sml parsing is https://github.com/dailab/libsml.

The Volkszähler guy told us, that thes shortly reinvented the wheel and did some work on smllib, but than decided to use the libsml, linked above.

In addition he mentioned jsml (https://www.openmuc.org/sml/) which is still better than starting from scratch.