* lily/tuplet-bracket.cc (calc_position_and_height): check musical

* lily/tuplet-bracket.cc (calc_position_and_height): check musical
slope against graphical slope.

* lily/ottava-bracket.cc (brew_molecule): support minimum-length
for ottava bracket.

* lily/side-position-interface.cc (general_side_position):
opps. reinstate *dir.

* lily/parser.yy: plug many memory leaks. We're down to 4 for each
parser run.

* lily/tuplet-bracket.cc: remove calc_dy ().

* Documentation/user/refman.itely (Balloon help): document balloon
help