Feature Tree colors

[ptc-4144934]

Allow users to add colors to the feature tree. Colors allow for a much more rapid search than names. Searching the names of features in a huge list is difficult when the tree gets long. The color could be added to the background of a feature line in a separate box or behind the text of the feature name. If it is possible to change the background then it may also be useful and/or necessary to change the font style also.

It is important to note that there should be 3 ideas pertaining to changing feature line colors:

1. The user should be able to edit the color of the block behind the text and font style of any feature in the tree
2. The user should be able to add a color block similar to the feature number in the tree
3. The user should be able to set up a color palette for each specific feature type, apply it, and then edit it independently if desired.

[ptc-6566506]

I would like to see a color differentiation in the Model Tree between non-regeneratable features due to a "read only" operation applied to a model and other regeneratable features.  It is not intuitive in which model(s) or at which feature that I have applied "read only" to a model.  I would also like to have ModelCheck query my model for the "read only" operation so I remember to decide whether I want the model to be saved/checked in with the "read only" operation not "cleaned".