Only one rule is applied in corpus-specific->UD conversion

[peterdekker]

When converting from corpus-specific to UD tags, only one mapping rule is applied. https://github.com/INL/clariah-fcs-endpoints/blob/master/src/main/java/org/ivdnt/fcs/mapping/ConversionEngine.java#L480

This can give strange results, for example giving "Neut" to a noun, without also giving "N": N(eigen,mv,dim):[Neut]

This might be solved by allowing multiple rules to be applied: but this gives new problems, because currently the program relies on just applying the most complex (longest) rule.
Another solution would be allowing multiple-to-multiple mappings, outputting multiple features in UD: #24