[iOS Dev] Parse query string into dictionary

Usage:

NSString *qs = @"username=hank&age=27&blog=whhnote.blogspot.com";
NSDictionary *queryParams = [self parseQueryString:qs];
NSLog(@"%@", queryParams);
NSLog(@"%@", [queryParams objectForKey:@"username"]); // get username from dict

So, you will get a dictionary look like

{
    age = 27;
    blog = "whhnote.blogspot.com";
    username = hank;
}