slic3r-tools updates

[limikael]

No description provided.

[limikael]

This update includes the merge of the following PRs from @mbenkmann:

limikael/freecad-slic3r-tools#8
limikael/freecad-slic3r-tools#9
limikael/freecad-slic3r-tools#10

[luzpaz]

@limikael no need to merge any changes from your repo in to FreeCAD-addons since the addon manager automatically gets the latest changes automagically. The addon manager will download the default specified 'master' branch (in quotations since some repos designate their dev branches as the default branch that users see when they visit the repo).

In other words, even if the Github Addon Manager repo is showing an obsolete commit as the latest commit, when a user activates the FreeCAD Addon Manager utility, the software redirects to the external Github repo of said dev and retrieves the most up to date changes. Does that make sense.

Every so often yorik or myself will run an update on the Github FreeCAD-addons repo to pull in said changes. But it's purely a cosmetic change.

[yorikvanhavre]

Sorry forgot to come look here guys.
Indeed FreeCAD always pushes the latest master branch from each addon, no matter what it says here on github (we basically just take the list of addons from here). So there is no need to update anything. But I'll merge your PR anyway just for the sake of it ;)