CSSSizeEditorModel.initialise
SizeEditorModel.prototype
CssSizeEditorModel constructor calls SizeEditorModel constructor
move generic methods into SizeEditorModel prototype
remove CssSize class
use this.size directly
rename cssSizeEditorModel to sizeEditorModel
only css-specific code left in CssSizeEditorModel,
rename CssSizeEditorView to SizeEditorView
ColorComponentEditorModel
colorType
ColorRange
return color component descriptions
ColorDenormaliser
hsl editing
remove trace statements
define some hsl colors
force output of HSL colours to style.css