Improve some comments about new file structure.

src/export.js

@@ -27,9 +27,9 @@ paper = new (PaperScope.inject(Base.exports, {
     window: window
 }))();
 
-// If we're on node, require some additional functionality now (PaperScript
-// support in require() with sourceMaps, and exportFrames / exportImage on
-// CanvasView)
+// If we're on node, require some additional functionality now before finishing:
+// - PaperScript support in require() with sourceMaps
+// - exportFrames / exportImage on CanvasView
 if (paper.agent.node)
     require('./node/extend')(paper);
 

src/init.js

@@ -10,8 +10,11 @@
  * All rights reserved.
  */
 
-// Node.js emulation layer of browser based environment, based on node-canvas
-// and jsdom.
+// Here we only make sure that there's a window and document object in the node
+// environment. We can't do this directly in src/paper.js, due to the nature of
+// how Prepro.js loads the include() files in the various scenarios. E.g. on
+// Node.js,only the files included in such a way see each other's variables in
+// their shared scope.
 
 /* global document:true, window:true */
 window = window || require('./node/window');