Generate .htaccess when upgrading from old versions

When upgrading from old ownCloud versions like 2.x the .htaccess is not
generated - which exposes the data to the internet. This fix will
generate a .htaccess when upgrading. (And no one exists)
Fixes #127

lib/base.php

@@ -221,6 +221,12 @@ class OC{
 			$installedVersion=OC_Config::getValue('version', '0.0.0');
 			$currentVersion=implode('.', OC_Util::getVersion());
 			if (version_compare($currentVersion, $installedVersion, '>')) {
+				// Check if the .htaccess is existing - this is needed for upgrades from really old ownCloud versions
+				if (isset($_SERVER['SERVER_SOFTWARE']) && strstr($_SERVER['SERVER_SOFTWARE'], 'Apache')) {
+					if(!OC_Util::ishtaccessworking()) {
+						OC_Setup::createHtaccess();
+					}
+				}		
 				OC_Log::write('core', 'starting upgrade from '.$installedVersion.' to '.$currentVersion, OC_Log::DEBUG);
 				$result=OC_DB::updateDbFromStructure(OC::$SERVERROOT.'/db_structure.xml');
 				if(!$result) {