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

include/graph.h

@@ -47,6 +47,7 @@ public:
 		NearestStyle,
 		LinearStyle,
 		LinearNonCyclicStyle,
+		BarStyle,
 		NumGraphStyles
 	};
 

include/knob.h

@@ -39,7 +39,7 @@ class textFloat;
 
 enum knobTypes
 {
-	knobDark_28, knobBright_26, knobSmall_17, knobGreen_17, knobStyled
+	knobDark_28, knobBright_26, knobSmall_17, knobGreen_17, knobVintage_32, knobStyled
 } ;