Fix IsEnabled binding.
Fix IsEnabled binding.

gep13/ChocolateyGUI,chocolatey/ChocolateyGUI,gep13/ChocolateyGUI,chocolatey/ChocolateyGUI,chocolatey/ChocolateyGUI,chocolatey/ChocolateyGUI,chocolatey/ChocolateyGUI,gep13/ChocolateyGUI,gep13/ChocolateyGUI,gep13/ChocolateyGUI