pbrd: Remove pbr_events

pbrd: Remove pbr_events

The pbr_events.c file was a mistake in that it overly complicated
the code and made it hard to think about what was happening.

Remove all the events and just do the work where needed.

Additionally rethink the sending of the pbr map to
zebra and only send one notification at a time instead
of having the sending function attempt to figure out
what to do.

Clean up some of the no form of commands to make them
work properly.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>
Signed-off-by: Don Slice <dslice@cumulusnetworks.com>