Update users that have Breeze as colorscheme to BreezeLight

This is something that @teams/vdg wants to do since BreezeLight
is the new default color scheme.
BUG:432470

misc/CMakeLists.txt

 add_subdirectory(qtcurvepreset)
 add_subdirectory(kde4breeze)
+add_subdirectory(breezetobreezelight)

misc/breezetobreezelight/CMakeLists.txt

+find_package(KF5ConfigWidgets REQUIRED)
+
+add_executable(breezetobreezelight main.cpp)
+
+target_link_libraries(breezetobreezelight KF5::ConfigWidgets)
+
+install(TARGETS breezetobreezelight DESTINATION ${KDE_INSTALL_LIBDIR}/kconf_update_bin/)
+install(FILES breezetobreezelight.upd DESTINATION ${KDE_INSTALL_KCONFUPDATEDIR})

misc/breezetobreezelight/breezetobreezelight.upd

+Version=5
+Id=BreezeToBreezeLight
+Script=breezetobreezelight

misc/breezetobreezelight/main.cpp

+#include <KColorScheme>
+#include <KConfig>
+#include <KConfigGroup>
+
+#include <QDebug>
+
+int main()
+{
+    KConfig globals("kdeglobals");
+    KConfigGroup general(&globals, "General");
+    if (general.readEntry("ColorScheme") != QLatin1String("Breeze")) {
+        return 0;
+    }
+    QString breezeLightPath = QStandardPaths::locate(QStandardPaths::GenericDataLocation, QStringLiteral("color-schemes/BreezeLight.colors"));
+    if (breezeLightPath.isEmpty()) {
+        return 0;
+    }
+    KConfig breezeLight(breezeLightPath, KConfig::SimpleConfig);
+    for (const auto &group : breezeLight.groupList()) {
+        auto destination = KConfigGroup(&globals, group);
+        KConfigGroup(&breezeLight, group).copyTo(&destination, KConfig::Notify);
+    }
+}