For now create targets a la "Qt5::Core" to stay compatible with the
current Qt5 naming scheme. The name is controllable via a CMake option.
Change-Id: If43c058221949b1900c2093f39ccc9d0f38028f1
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>
Introduce a new cached variable INSTALL_CMAKE_NAMESPACE for defining the
prefix used for CMake config files (c.f. "${PREFIX}Core/${PREFIX}CoreConfig.cmake")
Also make sure to `find_dependency(...)` the required packages inside
the individual CMake config files. I.e. in Qt5WidgetsConfig.cmake,
search for Qt5Core, etc. pp..
Change-Id: Idc027925fe9d5323091c4853803ad5ce44b1afc6
Reviewed-by: Jean-Michaël Celerier <jean-michael.celerier@kdab.com>
Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>