as discussed here: https://forum.freecadweb.org/viewtopic.php?f=35&t=53680&p=461356#p461349
* change default tolerance scale to 0.8
* the tolerance scale is directly applied, thus it must have non-italic label
* move tolerance scale to "Dimensions" tab
* move Fuzz settings to "Advanced" tab
* move Conventions to General tab since e.g. the projection angle is an important general setting
* add a note for the label font that this is also used for dimensions and that it there only has an effect for new ones
* use more useful step size of 0.1 for some scaling spinboxes
* sort UI fields in the C++ code to avoid doubled or missing entries (there were 2 doubled entries)
* uniform width of all preferences dialogs
* better alignment for the HLR dialog
At the moment one has to specify the LineGroup as string. But one doesn't know what groups exist. So one has to check the Wiki, learn there where the groups are defined and then open the definition file with a text editor.
This PR simplifies this by reading the existing groups out of the definition file and fill the combobox accordingly.
It also give the user info what the selected LineGroup defines via the tooltip.
A nice side effect is that no typos can occur since you don't have to enter the LineGroup name as text.
