XCF spec:
- Update to GIMP 2.8.10
- Clarify role of file formats in the save-vs.-export-context
- Rearrange outline
- Collect infos on basic concepts in one chapter
- Add table of contents
- Add File format version history
- Add note on image size
- Add open questions and TODOs
- Sort properties alphabetically
- Unify tiles and hierarchy examples
- Wording
- Cosmetic cleanups
Extract compositing.txt from xcf.txt
Update parasites.txt:
- Replace SVN->Git
- Update contact e-mail address
- Add table of contents
Cherry-picked from commit a83791be19
Sven Claussner