Move Material workbench preferences from FEM workbench to its own preferences page

[davesrocketshop]

Thank you for creating a pull request to contribute to FreeCAD! Place an "X" in between the brackets below to "check off" to confirm that you have satisfied the requirement, or ask for help in the FreeCAD forum if there is something you don't understand.

• Your Pull Request meets the requirements outlined in section 5 of CONTRIBUTING.md for a Valid PR

Please remember to update the Wiki with the features added or changed once this PR is merged.
Note: If you don't have wiki access, then please mention your contribution on the 1.0 Changelog Forum Thread.

---

[freecadci]

for feature branch PR_9210. Pipeline 830835044 was triggered at ed6a6b9. All CI branches and pipelines.

[sliptonic]

Is there an issue or forum topic where this was discussed?

[davesrocketshop]

I did see one a week or so ago where someone said they were going to do it but it was never done. I started a new thread: https://forum.freecad.org/viewtopic.php?p=673998#p673998

[freecadci]

for feature branch PR_9210. Pipeline 832018964 was triggered at 13ab05e. All CI branches and pipelines.

[freecadci]

for feature branch PR_9210. Pipeline 836934205 was triggered at d87beb9. All CI branches and pipelines.

[davesrocketshop]

Included bug fixes, usability enhancements (mostly bug fixes), and use of new preferences that allow external workbenches to add to the material search paths.

This is all outlined in the discussion thread: https://forum.freecad.org/viewtopic.php?p=673998

[freecadci]

for feature branch PR_9210. Pipeline 903667657 was triggered at b282edd. All CI branches and pipelines.

[davesrocketshop]

This pull request is now obsolete. It was intended as part of release 0.21, and quite frankly should have been in there.

This will now be addressed as part of the material overhaul