[Patterns] - Add guidelines around deletion

[mmenestr]

Original design issue: patternfly/patternfly-design#1163

Would like to document the work that was done in this issue above^.
Would create a new page under "Patterns" called Actions or something along those lines, where we could start by adding this deletion flow, and stronger recommendations around them. Also worth considering the information that exists in the modal guidelines that have some information about deletion modals.

[mmenestr]

@edonehoo talked to pankaj - assigning you to this now with the thought that you can include this as part of the "actions" page work!