Add namespace to KIFTypist to avoid collision with the original KIFTypist

If you include both PublicAutomation and  [KIF](https://github.com/kif-framework/KIF) ([where `KIFTypist` is from](https://github.com/kif-framework/KIF/blob/master/Classes/KIFTypist.h)) in your project then `KIFTypist` becomes defined twice, which makes Xcode unhappy. This "namespaces" `KIFTypist` to `PA_KIFTypist` and all references.