yoda2rio: ignore unhandled classes

Created by: lukasheinrich

yoda files are a concatenation of individual objects. If go-hep doesn't support all of them, I think it should just ignore the ones it doesnt and still convert the rest, otherwise you have to delete the unhandled ones by hand from the yodafile

Example: COUNTER object keep track of single floats and are frequently added to the yoda files Rivet produces