Reenabled Options Button

When refactoring the command margin code I switched from using a command
for the options button to just listening for the click event.  I failed
to remove the command from the XAML though and it caused the button to
be disabled
Exception in options caused VS crash

User reported an issue where hitting Ok on the options dialog caused
Visual Studio to crash.  While I was unable to reproduce this it's
pretty clear that the UpdateKeyBindings method was throwing an
exception.  It deals with a lot of COM objects, it's apparently capable
of throwing and sits on the core message loop.  Wrapped it with a try /
catch and reported the issue to the user