* scm/chord-name.scm (set-chord-name-style): new function.

	* scm/chord-name.scm (set-chord-name-style): new function.
	(new-chord-name-brew-molecule): revise to interpret markup only
	(new-chord->markup): cleanuppish rewrite. To be called from the
	new engraver.

	* lily/new-chord-name-engraver.cc: new engraver: call Chord ->
	Markup earlier, during interpreting.

	* input/test/{banter,jazz,american}-chords.ly (scheme): update
	style settings. Rename to chord-names-*.ly