fixed exec cmd in Install

SE/se-lib/Route/Install.php

@@ -278,8 +278,7 @@ jQuery(document).ready(function () {
 		$cmds[] = "echo `git show-ref --head|head -1|head -c 8` > SE/VERSION ";
 		$hasError = false;
 		foreach ($cmds as $cmd) {
-			$out = ''; $ret = '';
-			exec("cd {$installPath} && {$cmd}", $out, $ret);
+			V::exec("cd {$installPath} && {$cmd}", $out, $ret);
 			if (0 !== $ret) $hasError = true;
 			DBG::nicePrint($out, "cmd: `{$cmd}` (return:{$ret})");
 		}