Made the image accessible from outside class
Forward touch events to super
Removed uncommented code
Added a new export button
Refactored and added a new method to export the image
Set the export button enabled when we draw something
Set the export button disabled when we reset the context
Moved the method
interface builder stuff with the new export button and methods to it
Merge pull request #2 from simonwesterlund/master

Added functionality to export the drawn image to camera roll