Convert Q_FOREACH loops to C++11 for loops.

Q_FOREACH will de deprecated soon.

src/main.cpp

@@ -95,8 +95,8 @@ int main(int argc, char** argv)
     }
 
     if (config()->get("OpenPreviousDatabasesOnStartup").toBool()) {
-        QStringList filenames = config()->get("LastOpenedDatabases").toStringList();
-        Q_FOREACH (const QString& filename, filenames) {
+        const QStringList filenames = config()->get("LastOpenedDatabases").toStringList();
+        for (const QString& filename : filenames) {
             if (!filename.isEmpty() && QFile::exists(filename)) {
                 mainWindow.openDatabase(filename, QString(), QString());
             }