Add Capability to open Bambu Studio 3MFs

[csweeney0926]

I occasionally get requests to print items that are posted on Maker World (Bambu's version of Pintables). For some files a stl is not available and only a 3mf or Bambu studio file can be downloaded. Prusa slicer is not able to open 3MF files from Bambu Studio (they added some feature that isn't compatible with the current Prusa Slicer Versions. For these files I have to open them in Bambu Studio, export as an STL and then import the STL into Prusa Slicer which is a lot of extra steps.

It would be nice if Prusa Slicer could open or convert Bambu Studio 3MFs into STLs directly. As Maker World gets a larger library and more people use it I expect this problem will pop up for more people more often.