Cleaned out the old theme code and moved padding and margins to theme

artist/patterns/uniform.go

@@ -12,3 +12,16 @@ type Uniform color.RGBA
 func (pattern Uniform) Draw (destination canvas.Canvas, clip image.Rectangle) {
 	shapes.FillColorRectangle(destination, color.RGBA(pattern), clip)
 }
+
+// Uhex creates a new Uniform pattern from an RGBA integer value.
+func Uhex (color uint32) (uniform Uniform) {
+	return Uniform(hex(color))
+}
+
+func hex (color uint32) (c color.RGBA) {
+	c.A = uint8(color)
+	c.B = uint8(color >>  8)
+	c.G = uint8(color >> 16)
+	c.R = uint8(color >> 24)
+	return
+}

config/config.go

@@ -2,15 +2,6 @@ package config
 
 // Config can return global configuration parameters.
 type Config interface {
-	// Padding returns the amount of internal padding elements should have.
-	// An element's inner content (such as text) should be inset by this
-	// amount, in addition to the inset returned by the pattern of its
-	// background.
-	Padding () int
-	
-	// Margin returns how much space should be put in between elements.
-	Margin () int
-
 	// HandleWidth returns how large grab handles should typically be. This
 	// is important for accessibility reasons.
 	HandleWidth () int