added support for extended legth on unknown attributes

Feature/sendbuffer plus some refactoring

AdjRIBOut: Don't add PathIdentifier without AddPath capabilities and don't add path twice.

Signed-off-by: Maximilian Wilhelm <max@sdn.clinic>

BGPPath.insertNewASSequence() should extend the path in place.

Signed-off-by: Maximilian Wilhelm <max@sdn.clinic>

Feature/unknown attr pass

Unfuck iBGP vs. eBGP handling

Signed-off-by: Maximilian Wilhelm <max@sdn.clinic>

  This code previously failed to remove and therefore withdraw routes from
  non AddPathRX capable neighbors as there could no PathID be found for them.

Signed-off-by: Maximilian Wilhelm <max@sdn.clinic>

Signed-off-by: Maximilian Wilhelm <max@sdn.clinic>

Signed-off-by: Maximilian Wilhelm <max@sdn.clinic>