Revision control
++ QT += widgets
++ requires(qtConfig(combobox))
++
++ HEADERS = renderarea.h \
++ window.h
++ SOURCES = main.cpp \
++ renderarea.cpp \
++ window.cpp
++ RESOURCES = basicdrawing.qrc
++
++ # install
++ target.path = $$[QT_INSTALL_EXAMPLES]/widgets/painting/basicdrawing
++ INSTALLS += target