Added "Web Safe" URL encoding support
Added NSString methods:
+(NSString *)stringFromBase64UrlEncodedString:(NSString *)base64UrlEncodedString;
-(NSString *)base64UrlEncodedString;
Added NSData methods:
+(NSData *)dataWithBase64UrlEncodedString:(NSString *)base64UrlEncodedString;
-(NSString *)base64UrlEncodedString;
Added MF_Base64Codec utilities:
+(NSString *)base64UrlEncodedStringFromBase64String:(NSString *)base64String;
+(NSString *)base64StringFromBase64UrlEncodedString:(NSString *)base64UrlEncodedString;