Ensure backward compatibility and some cosmetic changes.

README.md

@@ -39,11 +39,12 @@ The SingleApplication class implements a `showUp()` signal. You can bind to that
 Note that since `SingleApplication` extends the `QApplication` class  you can do the following:
 ```cpp
 // Truly raise your window.
-QObject::connect(&app, &SingleApplication::showUp, [&]{
-        window.show();
-        window.raise();
-        window.activateWindow();
-    }); // 'window' is your QWindow instance
+QObject::connect(&app, &SingleApplication::showUp, [&]
+{
+    window.show();
+    window.raise();
+    window.activateWindow();
+}); // 'window' is your QWindow instance
 ```
 
 Using `QApplication::instance()` is a neat way to get the `SingleApplication` instance at any place in your program.

singleapplication.cpp

@@ -115,7 +115,7 @@ SingleApplication::SingleApplication(int &argc, char *argv[])
         // terminated.
         if( d->socket->waitForConnected(100) )
         {
-            // Terminate the program using STDLib's exit function.
+            // Terminate the program using STDLib's exit function
             ::exit(EXIT_SUCCESS);
         } else {
             delete d->memory;

singleapplication.h

@@ -2,6 +2,10 @@
 #define SINGLE_APPLICATION_H
 #include <QtCore/QtGlobal>
 
+#ifndef QAPPLICATION_CLASS
+  #define QAPPLICATION_CLASS QApplication
+#endif
+
 #include QT_STRINGIFY(QAPPLICATION_CLASS)
 
 class SingleApplicationPrivate;