Remove usages of .Tag on ComboBox theme

[ButchersBoy]

• ComboBox theme (ComboBoxItem.Tag)
• Also, TreeView theme, but lower priority as on more of a hidden element.

Should remove this as we are blocking people from using .Tag for their own purposes, and replace with an attached property.

Either:

• Add
  • ComboBoxAssist.HideItem : bool
  • TreeViewAssist.HeightFactor : double
• Or a single MaterialDesign.FrameworkTag : object

I think I prefer the former, more verbose option, even though it creates more classes...

[l1pton17]

But treeview uses inner scrollviewer's tag, that is not a part of open properties.
I mean template doesn't use TreeViewItem.Tag.

[ButchersBoy]

Sorry, my mistake...

But did you see #159 ?

[l1pton17]

@ButchersBoy yes, i will fix it in a few days

[ButchersBoy]

Cool, thanks, I'll mark as in progress and leave to you.