Also import `DraftGeomUtils` where necessary.
These modules were previously imported globaly when the base
`DraftTool` class was first called by the individual tools
through the `Creator` and `Modifier` classes.
However, since `DraftTool` was moved to a separate module,
these `Part` and `DraftGeomUtils` modules are no longer
in the `DraftTools` namespace, and therefore they
cannot be imported globally anymore.
Now the `Part` and `DraftGeomUtils` modules are imported
in the specific functions where they are actually needed.
This is the base class of most Draft Gui Commands,
particularly those which were developed a long time ago.
It is inherited by `Creator` and `Modifier`
to set some specific options for some tools.
Newer Gui Commands do not use these classes and thus
are independent of `DraftTool`.
Nevertheless, in the future we expect to organize further
the commands so that they all derive from a few classes,
so that they all share some common properties and behaviors.