Streamlined score manager hidden menu.

Current score manager hidden menu:

    Score manager - active scores - hidden commands

        code location - edit (here)
        code location - where (where)
        where-tracking - toggle (wtt)

        display hidden menu (hidden)
        execute statement (exec)
        go back (b)
        go home (home)
        go home (H)
        go to current score (score)
        go to current score (S)
        go to next score (next)
        go to prev score (prev)
        quit (q)
        toggle menu commands (tmc)
        view LilyPond log (log)

        cache - view (cv)
        cache - write (cw)

        repository - add (radd)
        repository - commit (rci)
        repository - status (rst)
        repository - update (rup)

        scores - show all (ssl)
        scores - show active (ssv)
        scores - show mothballed (ssmb)

        tests - doctest (tdoc)
        tests - py.test (tpy)

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