canonindices should canonically order multiple gaps or knobs

[jeisner]

[item from the old TO-DO file dated 2002-04-07]

canonindices really should deal with the problem of multiple gaps or knobs on a single constituent: these should be alphabetized or something, with ties broken by where they are first matched.

[jeisner]

[item from the old TO-DO file dated 2002-04-07]

listframes should give a canonical numbering to the slashed categories.