Adding WKWebView support

[superarts]

When I'm adding support for WKWebView so that my app supports iOS 7 and iOS 8 at the same time, I found it's possible to add most of my changes on the app side, mostly including handling jockey://event/xxx messages with my own code. Surely it would be good to add this to Jockey but it will involve some interface changes. Anyhow, the only change I need to made to Jockey is the + (void)send:(NSString *)type withPayload:(id)payload toWebView:(UIWebView *)webView call. When I need to send from app to web, the receiver has to be a UIWebView. So I added minimal modification by making it's possible to pass a WKWebView as a UIWebView (of course in this case either a protocol should be created or the type should be simply changed to id, but I don't want to change too much to exisiting Jockey).

Cheers.

[t2ac32]

si jockey does support mkwebview?¿? i didn't quite get how to enable it.