Waveshaper updates: added amplitude +/- buttons, toggle led to clip inpu...

...t to 0dB, more helpful gridlines in wavegraph

Mallets: artwork update by Bill Y.
New knob: knob_vintage32, currently only used in Mallets, can be used for other things in the future (maybe if we get some more vintage-style synths/effects?)
Graph widget: added new drawing mode (bar style graph) for future use, currently unused anywhere, have plans