change project structure for 2.0 version
rework project to use multiple targets and improved organization

- library images are now stored in a bundle
- the demo project has been updated to Xcode 5 default settings
move project contents up one level
change file structure following recommended cocoapod practices
setup demo project using development pod installation
remove instances of 'FGallery' and replace with 'GDIImageGallery'
fix warning about uninitialized number