Bug 4957 TxChainManager lifecycle startup cleaning

 - when proceeding connectionContext to deviceManager
   we rely on fact that for given nodeId there must NOT
   exist deviceContext. If there is one then connection
   will be refused because previous session is not fully
   tore down
 - any exceptions thrown by proceeding connectionContext
   will result into disconnection
 - first thing to do for new deviceContext is to build up
   close mechanism

Change-Id: I860768c69849652d36ed9078016ffd9bf5f20c6a
Signed-off-by: Jozef Bacigal <jbacigal@cisco.com>