Bug-2225 Update PCEP segment routing according draft version 00.
reference: http://tools.ietf.org/html/draft-ietf-pce-segment-routing-00
-removed "02" suffix from package names, class names and yang filed
-added SR RRO Subobject model, parser/serializer and tests
-added new PCEP errors
-removed unnecessary PCEP messages extensions
-removed F and S flags from Subobject model - can be determined from context
Change-Id: Iac566fea7b3f74e0bd61341306ac5a5e46bbf15e
Signed-off-by: Milos Fabian <milfabia@cisco.com>