Use cairo context wrapper for fill colors on marketing

Actually deliver what I promised

Fixes #71

lib/squib/graphics/hand.rb

@@ -1,3 +1,5 @@
+require 'squib/graphics/cairo_context_wrapper'
+
 module Squib
   class Deck
 
@@ -29,8 +31,8 @@ module Squib
         end
       end
       x, y, w, h = cxt.target.ink_extents # I love Ruby assignment ;)
-      png_cxt = Cairo::Context.new(Cairo::ImageSurface.new(w + 2*margin, h + 2*margin))
-      png_cxt.set_source_color(fill_color)
+      png_cxt = Squib::Graphics::CairoContextWrapper.new(Cairo::Context.new(Cairo::ImageSurface.new(w + 2*margin, h + 2*margin)))
+      png_cxt.set_source_squibcolor(fill_color)
       png_cxt.paint
       png_cxt.translate(-x + margin, -y + margin)
       png_cxt.set_source(cxt.target)

lib/squib/graphics/showcase.rb

@@ -1,3 +1,5 @@
+require 'squib/graphics/cairo_context_wrapper'
+
 module Squib
   class Deck
 
@@ -16,8 +18,9 @@ module Squib
       out_width = range.size * ((@width - 2*trim) * scale * offset) + 2*margin
       out_height = reflect_offset + (1.0 + reflect_percent) * (@height - 2*trim) + 2*margin
       out_cc = Cairo::Context.new(Cairo::ImageSurface.new(out_width, out_height))
-      out_cc.set_source_color(fill_color)
-      out_cc.paint
+      wrapper = Squib::Graphics::CairoContextWrapper.new(out_cc)
+      wrapper.set_source_squibcolor(fill_color)
+      wrapper.paint
 
       cards = range.collect { |i| @cards[i] }
       cards.each_with_index do |card, i|