produces minute differences where there should be none.
- scripts/ppmdiff/ppmdiff.c (diff): instead of looking for all or noting
changes, also detect gradual changes
- scripts/ppmdiff/ppmdiff.c (diff, main): don't mark areas with differences
in the main images if using shadow images
- scripts/schps2ppm: new option to disable alpha blending
- scripts/schhist2web: cache pixmaps with default line thickness and no
alpha blending in hard_*
- scripts/schhist2web: base marking of areas with differences exclusively
on the hard_* pixmaps
- scripts/normalizeschps: don't edit in place and thus become capable of
running in a pipe
- scripts/schps2ppm: considered - to be an option and thus didn't accept
it as input file name
- scripts/schhist2web: open-coded functionality of "gitsch2ppm"
- scripts/gitsch2ppm: removed