Bug 187 - PCEP: object parser - report correctly unknown objects

-differs between unknown object-class and object-type, returns proper error

Change-Id: I04c5f274294793776c84c4de8875e22d71b9a650
Signed-off-by: Milos Fabian <milfabia@cisco.com>
Merge "Bug 187 - PCEP: object parser - report correctly unknown objects"