Add missing libreoffice deps

This pullrequest adds all missing dependencies to build libreoffice.

Please note, that I added an icu-49 package. I'm not perfectly sure whether I should add a conflict here. (for icu-49 and -devel. icu-49-libs is fine though.)

The next pullrequest will add libreoffice itself and the language packs. I still have to work out subpackages and *.desktop stuff.