A lot of crap to get simple dialogs to work with colors. Fixes #1234
Force content of SimpleDialogs to bind.

Fixes #1238
Changed the way ProgressForeground was set. It may help with #1149
fix attached properties
Merge pull request #1246 from MahApps/1245-punker76-FocusBorderBrush-TextboxHelper

fix attached properties MouseOverBorderBrush,FocusBorderBrush on TextboxHelper
Merge pull request #1239 from Amrykid/dialogs-patch-something

[WIP] Amrykid's Super Awesome Dialog Patch