Help: clarify relation between CPackIFWGenerator, CPackIFW, and QtIFW.
- Show external link only once per page
- Explain abbreviation QtIFW
- Explain relation between CPackIFWGenerator and CPackIFW
- Add link to cpack-generators(7) [which should acquire an "Overview" section ...]
- Rephrase overviews for conciseness
Backport: release
Topic-rename: cpack-ifw-qt-links
Edited by Brad King