Lemma for ordinals

[kscanne]

I'd like to make these consistent across the the treebank... at present, ordinals like "tríú", "ceathrú", "cúigiú" are sometimes taken as the lemma themselves, but other times lemmatized to "trí", "ceathair", "cúig". I'd be in favor of treating them as lemmas:

• these are all headwords in the standard Irish dictionaries — I'd consider "cúig" -> "cúigiú" as a case of derivational morphology at best
• the English/French treebanks I looked at treat ordinals as their own lemmas
• the Irish treebank already does this consistently for "céad" and "dara", so no change would be needed in the most common cases