Added ability to implement UIWebViewDelegate's delegates

(cherry picked from commit a947d6c081e4d1985dbb440f3c82bc92503db112)
Updating names for delegate callback

Clashes with default UIWebView's callback names

(cherry picked from commit 2149d3b987979a36bce19f8bb08859b7554a5e17)
Added support for missing UIWebViewDelegate method to SVWebViewDelegate