Changes mainly to OC-Supported-Features.

Signed-off-by: Jouni Korhonen <jouni.korhonen@broadcom.com>
Added a bit of initial text into Section 5.5.2.
Clarified that only the reporting node includes the OC-OLR int
o Diameter messages.

Signed-off-by: Jouni Korhonen <jouni.korhonen@broadcom.com>