fix when $_SERVER['HTTPS'] is "ON"

when $_SERVER['HTTPS'] is "ON" it doesn't work well

framework/yii/web/Request.php

@@ -668,8 +668,8 @@ class Request extends \yii\base\Request
 	 */
 	public function getIsSecureConnection()
 	{
-		return isset($_SERVER['HTTPS']) && ($_SERVER['HTTPS'] === 'on' || $_SERVER['HTTPS'] == 1)
-			|| isset($_SERVER['HTTP_X_FORWARDED_PROTO']) && $_SERVER['HTTP_X_FORWARDED_PROTO'] === 'https';
+		return isset($_SERVER['HTTPS']) && (strcasecmp($_SERVER['HTTPS'],'on') || $_SERVER['HTTPS'] == 1)
+			|| isset($_SERVER['HTTP_X_FORWARDED_PROTO']) && strcasecmp($_SERVER['HTTP_X_FORWARDED_PROTO'],'https');
 	}
 
 	/**