Revert "Merge pull request #69 from emartynov/master"

This reverts commit ecc417140afab8c610be3d4f7e60534817f018f7, reversing
changes made to 052f5885f7da9ddf5c39befc95e35c623d6d5358.
Rename and tweak category method to retrieve arguments from NSInvocation.

In particular, keep it from stopping when encountering an unknown argument type.
Instead, log it and use NSNull as the argument.
Release 1.3.0
Increased deployment targets to OS X 10.8, iOS 6.0
Tweaking podspec
Fix README reference to latest release of OCHamcrest