[OSX, docs] updating some release build informations

As far as i can see, everything ist 64bit only:

    Jonass-MacBook-Pro-3:MacOS jonasschnelli$ lipo -info ../Frameworks/libcrypto.1.0.0.dylib 
    Non-fat file: ../Frameworks/libcrypto.1.0.0.dylib is architecture: x86_64
    Jonass-MacBook-Pro-3:MacOS jonasschnelli$ lipo -info Bitcoin-Qt 
    Non-fat file: Bitcoin-Qt is architecture: x86_64