Added post-insertion and deletion hooks to TypedCollection.

These can be overriden to set or unset a note head's client chord when adding
or removing note heads to that chord's note head inventory.
Removed all list-interface methods from Chord.

Please operate on the note head inventory available at Chord.note_heads
instead.

Chord's interface now consists of these:

    get_note_head(pitch)
    lilypond_duration_multiplier
    lilypond_format
    note_heads
    override
    select([sequential])
    set
    sounding_pitches
    storage_format
    written_duration
    written_pitch_indication_is_at_sounding_pitch
    written_pitch_indication_is_nonsemantic
    written_pitches
    __copy__(*args)
    __eq__(expr)
    __mul__(n)
    __ne__(expr)
    __repr__()
    __rmul__(n)
    __str__()

Not bad!
Removed **kwargs from all Component subclasses.

All tests pass. It appears this functionality was unused.
Improved viewcode formatting in the docs.
Merge branch 'master' of https://github.com/Abjad/abjad

Conflicts:
	trunk/abjad/tools/iotools/count_function_calls.py