Take inspiration from debian and append -qt5 suffix to the library name
for the qt5 FLAVOR.
Split the common headers/manpages/doc into a separate subpackage, put
the library/qt files in another subpackage that depende on the latter
(and that doesnt conflict with 'the other flavor', and finally add the
correct @conflict/@pkgpath markers for proper upgrade path.
Most of the work done by rsadowski@, i just did the polishing with help
from espie@
ok rsadowski@
143533d8fc