Description of problem:
Beaker automatically adds certain kernel command line options like ksdevice=bootif during kickstart.  Occasionally I need to remove one of those options for testing, and I thought the only way was to set up my own PXE server.  I learned today there is a hidden (or not well documented) feature of adding the option with a ! prefix to disable it.  For example, this will remove the option:

  <recipe ... kernel_options="!ksdevice=bootif" ...>

Please update the documentation to show this method.

Version-Release number of selected component (if applicable):
Beaker 26.4