basic rfc1997 (well known communities) filter, code deduplication

Feature/community support

BGP large community support

fixed test name

unified error message

simplification

Use native ticker instead of resetting timer

Feature: support AS4path and AS4aggregator ( RFC 6793 )

Feature: Added basic community support

Feature: Added support for RFC 8203 in notification decoder

Feature: Only activate the fsm at configurable reconnectInterval

Fix: Added missing mandatory LocalPref

Feature: Use logrus everywhere instead of fmt.Printf

Fix: Don't announce own ASN in ASPath if iBGP

Feature: allow users to use filters infront of loc rib

Fix: Deadlock in locRIB

Release lock after updating map. UpdateNewClients may call GetOptions or Clients() and thus cause a deadlock