Collect useful commits from other forks and package it in a pull request.

Hi,

I went through a few forks that have reasonable commits which are useful for everyone and merged them in my fork.
This pull request should merge changes of the following repos:

https://github.com/baldmountain/Cocoa-Touch-Barcodes/ by @baldmountain
https://github.com/baz/Cocoa-Touch-Barcodes/ by @baz
https://github.com/netshade/Cocoa-Touch-Barcodes/
https://github.com/openresearch/Cocoa-Touch-Barcodes/

Tell me what you think about it.