Properly import the tracker classes. Avoid star imports,
and use the classes prefixed with the name of the module.
The BIM Workbench also has to be updated to use the new
module.
```
import draftguitools.gui_trackers as DraftTrackers
```
And do not load the `Snapper` in `DraftGui`.
The Snapper should be initialized by the module
that imports `DraftGui`, most probably `DraftTools`
or even by the `InitGui` of the workbench.
It replaces the older `Draft_Array` command, and provides
a task panel to select the properties, similar to the
`Draft_PolarArray` and `Draft_CircularArray` commands.
It can also create `App::Links` directly from this task
panel, so it also replaces the `Draft_LinkArray`
introduced by the LinkMerge.
