Modifications for optionally accepting common typos.
Move verbs ending with -lA to another lexicon.

        Currently we do not analyze the derivational suffix -lA, but
        list all stems observed so far in the lexicon. This change
        moves verbs ending -lA into separate lexicon for preparation
        of optionally analyzing the -lA derivation. The new lexicon
        file `verb_la' needs a review before doing so.
Lexicon additions/updates.
Documentation update: mostly style/typological changes.