Update TreeFlower 3 artistic motif directory structure:
- Move `TreeFlower/3/Distro/5.5/Media' up to `TreeFlower/3/Media'
and remove `TreeFlower/3/Disto/5.5' directory.
- Installation media images, based on TreeFlower 3 artistic motif,
are rendered using the
`trunk/Identity/Images/Themes/TreeFlower/3/Media' directory as
source and the `--releasever' and `--basearch' options to
control the release and architecture the images are produced
for.