Make fileinfo extension optional

app/install.php

@@ -465,7 +465,7 @@ function printStep1() {
 	<?php if ($res['fileinfo'] == 'ok') { ?>
 	<p class="alert alert-success"><span class="alert-head"><?php echo _t('gen.short.ok'); ?></span> <?php echo _t('install.check.fileinfo.ok'); ?></p>
 	<?php } else { ?>
-	<p class="alert alert-error"><span class="alert-head"><?php echo _t('gen.short.damn'); ?></span> <?php echo _t('install.check.fileinfo.nok'); ?></p>
+	<p class="alert alert-warn"><span class="alert-head"><?php echo _t('gen.short.damn'); ?></span> <?php echo _t('install.check.fileinfo.nok'); ?></p>
 	<?php } ?>
 
 	<?php if ($res['data'] == 'ok') { ?>

lib/lib_install.php

@@ -67,7 +67,7 @@ function checkRequirements($dbType = '') {
 		'favicons' => $favicons ? 'ok' : 'ko',
 		'http_referer' => $http_referer ? 'ok' : 'ko',
 		'message' => $message ?: 'ok',
-		'all' => $php && $minz && $curl && $pdo && $pcre && $ctype && $fileinfo && $dom && $xml &&
+		'all' => $php && $minz && $curl && $pdo && $pcre && $ctype && $dom && $xml &&
 		         $data && $cache && $users && $favicons && $http_referer && $message == '' ?
 		         'ok' : 'ko'
 	);