ToolsTree= is now just a regular universal setting so no need to
document it as being special in the ToolsTree= documentation.
If set to `default`, **mkosi** will automatically add an extra tools tree
image and use it as the tools tree.
- Note that **mkosi** will only build a single default tools tree per build,
- even if multiple images are defined in `mkosi.images` with
- `ToolsTree=default`. The settings of the "last" image will apply to
- the default tools tree (usually the image defined last in
- mkosi.images and without any dependencies on other images).
-
The following table shows for which distributions default tools tree
packages are defined and which packages are included in those default
tools trees: