Update SingleApplication to upstream master

SingleApplication/examples/basic/CMakeLists.txt

@@ -0,0 +1,12 @@
+cmake_minimum_required(VERSION 3.7.0)
+
+project(basic LANGUAGES CXX)
+
+# SingleApplication base class
+set(QAPPLICATION_CLASS QCoreApplication)
+add_subdirectory(../.. SingleApplication)
+
+add_executable(basic main.cpp)
+
+target_link_libraries(${PROJECT_NAME} SingleApplication::SingleApplication)
+

SingleApplication/examples/basic/main.cpp

@@ -5,5 +5,7 @@ int main(int argc, char *argv[])
     // Allow secondary instances
     SingleApplication app( argc, argv );
 
+    qWarning() << "Started a new instance";
+
     return app.exec();
 }