fixes #646

change regex by using well tested regex from here:
https://mathiasbynens.be/demo/url-regex

by @diegoperini
https://gist.github.com/dperini/729294

lib/Froxlor/Validate/Form/Data.php

@@ -152,7 +152,7 @@ class Data
 			return false;
 		}
 
-		$pattern = "/^https?:\/\/[a-zA-Z0-9\-\.]+\.[a-zA-Z]{2,4}(\:[0-9]+)?\/?(.+)?$/i";
+		$pattern = '%^(?:(?:https?)://)(?:\S+(?::\S*)?@)?(?:(?!10(?:\.\d{1,3}){3})(?!127(?:\.\d{1,3}){3})(?!169\.254(?:\.\d{1,3}){2})(?!192\.168(?:\.\d{1,3}){2})(?!172\.(?:1[6-9]|2\d|3[0-1])(?:\.\d{1,3}){2})(?:[1-9]\d?|1\d\d|2[01]\d|22[0-3])(?:\.(?:1?\d{1,2}|2[0-4]\d|25[0-5])){2}(?:\.(?:[1-9]\d?|1\d\d|2[0-4]\d|25[0-4]))|(?:(?:[a-z\x{00a1}-\x{ffff}0-9]+-?)*[a-z\x{00a1}-\x{ffff}0-9]+)(?:\.(?:[a-z\x{00a1}-\x{ffff}0-9]+-?)*[a-z\x{00a1}-\x{ffff}0-9]+)*(?:\.(?:[a-z\x{00a1}-\x{ffff}]{2,})))(?::\d{2,5})?(?:/[^\s]*)?$%iuS';
 		if (preg_match($pattern, $url)) {
 			return true;
 		}