Menu- add optional danger state for menu items

[mcarrano]

Want to allow for applying "danger' styling to menu items.

Core PR: patternfly/patternfly#5102

[gefgu]

I would like to work on this issue :)

[mcarrano]

@nicolethoen @tlabaj ^^^

[tlabaj]

@gefgu I have assigned you. Thank you for picking up the issue. The target code freeze date for this feature is October 19th.