added explicit return type for Web.getCookies (fixed issue #1696)

std/neko/Web.hx

@@ -164,7 +164,7 @@ class Web {
 		Returns an hashtable of all Cookies sent by the client.
 		Modifying the hashtable will not modify the cookie, use setCookie instead.
 	**/
-	public static function getCookies() {
+	public static function getCookies():haxe.ds.StringMap<String> {
 		var p = _get_cookies();
 		var h = new haxe.ds.StringMap<String>();
 		var k = "";

std/php/Web.hx

@@ -252,7 +252,7 @@ class Web {
 		Returns an hashtable of all Cookies sent by the client.
 		Modifying the hashtable will not modify the cookie, use setCookie instead.
 	**/
-	public static function getCookies() {
+	public static function getCookies():haxe.ds.StringMap<String> {
 		return Lib.hashOfAssociativeArray(untyped __php__("$_COOKIE"));
 	}