reorganize project folder using synx see #1

@hiyahiyao, from now you should use synx: https://github.com/venmo/synx
remove useless image folder ressource #1

in this case, images should be stored in xcode xcasset folder
category model: rename attributes #1
category cell: prepare for migration #1

+ we will use SDImage downloader to set the category image from an URL
+ update category title to the updated model
custom view: remove IBAction declarations #1

there is no need to declare method signatures in the implementation
file.
custom view: remove useless newlines see #1
rename default vc to root vc see #1
root vc: add code indentation see #1
root vc: remove commented code
root vc: remove unimplemented delegate methods #1
root vc: cosmetic changes #1
declare global static string for cell id #1
category cell: rename title label property #1
category cell: rename class name see #1
remove deployment target warning see #1
update category cell identifier name see #1
rename scaffold category model class see #1