Updating the command parameter binding for the ColorCommand property so null isn't being passed as the parameter value.

[smeddows]

Description of Change

Fixing the broken binding that was always passing null into the command. Explicitly stated the element name and then passed in the 'Background' property. Cast the parameter in the code behind with the Command

Bugs Fixed

This should fix the issue found in (Issue #144)[https://github.com/microsoft/XamlBehaviorsWpf/issues/144].

Changed:

• void Execute(object parameter)
• InvokeCommandControl.xaml

Behavioral Changes

No changes to behavior are expected.