Merge branch 'master' into ben-work-in-progress
Added abatement section, new definitions

Added a section on throttling and diversion, and discussed
architectural principles. Still need to add agent behavior discussion,
and remove redundancies with prior text.
Remove redundante text

Remove text from the Diameter Routing section that is redundant with
the new “Overload Abatement” section. Also fixed random misspelling of
“Diameter”.
removed ToDo entry

Removed ToDo entry that was handled in previous commit.
relay behavior guidelines

Added “DOIC Behavior at Relays” section that offers very high level
(and somewhat abstract) guidelines about how relays should handle OLRs.
Merge branch 'ben-work-in-progress'