Refactors the Dictionary extension to be conditional on keys and values being strings, and uses URLComponents/URLQueryItem for the escaping. This obviates the need for the URL encoding method on String.
Changes the NSMutableURLRequest extension to be on URLRequest instead, with a mutating method (and change the parameter on an HTTPConditionalGetInfo method to inout).
Changes some getter-like functions to computed properties.
Dictionaryextension to be conditional on keys and values being strings, and usesURLComponents/URLQueryItemfor the escaping. This obviates the need for the URL encoding method onString.NSMutableURLRequestextension to be onURLRequestinstead, with amutatingmethod (and change the parameter on anHTTPConditionalGetInfomethod toinout)."&".)