fix for BUG-709 - connectionCookie generate, use

- session cookie is based on datapathId only (not exposed, based in BigInteger)
- connection cookie is based on auxiliaryId, unique hashed key is exposed

Change-Id: Ifc293f876b3e57be38622141e92f8cdb0e47d056
Signed-off-by: Michal Rehak <mirehak@cisco.com>