Revert "avoid to install the library only needed for unit tests"
Revert "avoid to install the library only needed for unit tests"

k, dumb idea, kills qobject_cast and so on ;)

This reverts commit da75affd55daff2305e86ee9c6773edaeef8416c.

jfmcarreira/kate,DickJ/kate,sandsmark/kate,DickJ/kate,sandsmark/kate,sandsmark/kate,jfmcarreira/kate,DickJ/kate,DickJ/kate,sandsmark/kate,cmacq2/kate,cmacq2/kate,jfmcarreira/kate,cmacq2/kate