Check mark on menu bar pull down item?

[Eric Frans <epfrans(at)west.raytheon.com>]

Hello IDL folks,

I have looked through the documentation for IDL 5.1 and can't seem to
find any mention of how to display a check mark next to a pull down item
from a menu bar.  It looks like IDL leaves room on the left of menu bar
pull down items for this purpose, but I can't figure out how to
implement it.  I hope this is possible because it would be a lot slicker
than having to use check boxes in the main widget area to indicate that
certain options are on or off.

As always, thanks in advance for any help!

	- Eric Frans