Model browser folder icons

[karl.lednik]

When all items in a folder are suppressed or invisible, the appearance of the folder icon and/or name should change accordingly.  Bonus points for another appearance for when only some contents are suppressed or invisible.  

See the folder icons in SolidWorks as an example;

• Blue is enabled
• Gray is suppressed
• Blue/grey is a mix

(Never mind the errors... our SW models are a mess)

[Yijiang.Cai]

Many thanks for posting the idea, and tracked as [INVGEN-70482].

Besides the enabled, suppressed & mixed state, I suppose we also need to consider the visibility, grounded, adaptive & transparent states here.