update readme
sprayBrush density of 15 is ok on performance
brushes to be implemented
vertical line brush
up version
implement horizontalLineBrush
simplify shaped brush drawing
remove rect-circleBrush
circleShapedBrush
use lineShapeBrush
remove line-circleBrush
wrong name: lineShapeBrush -> lineShapedBrush
use shape brush
remove unneeded modules
use pencilShapedBrush
remove unneeded modules
more simplification
remove lineShapedBrush
not using circleShapedBrush
remove circleShapedBrush