Updated RBStoryboardLink to support iOS 7.

Fixes issue #7. Dropped iOS 5 due to technical issues and iOS 6 for simplicity. Also, updated copyright dates.
Fixed an infinite recursion crash.
Updated the pod spec.
Added UI tests to the samples.

Also, changed the samples to use RBStoryboardLink as a CocoaPod.
Updated the README.
Added lock file for verioning of pods
Added missing plist file
Merge branch 'master' into robbrown