This helps to build single apps without having full KF5, e.g. Windows
- X11 -> only try to find on !win32 and !mac
- Qt5:
- Sql -> sheets
- X11Extras -> require globally when X11 is found and !win32 and !mac
- KF5:
- Kross -> globally optional
- not needed: Emoticons
- Codecs -> kexi
- ConfigWidgets -> kexi, kundo2
- GlobalAccel -> krita/ui
- GuiAddons -> plan
- Parts -> plan
- Sonnet -> koodf, sheets
- TextEditor -> kexi
- TextWidgets -> kexi, kotext
- ThreadWeaver -> sheets, libs/widgets/tests
- Wallet -> optional, in koodf and kostore; don't compile encryption if Wallet is missing
- WidgetsAddons -> kexi
- use REQUIRED_QT_VERSION and MINIMUM_KF5_VERSION consistently
- consistently use SHOULD_BUILD_APP_STAGE and SHOULD_BUILD_APP_SHEETS
- update dependencies in other places