decorate structured syslog based on application if needed
decorate structured syslog based on application if needed

normally structured syslog is decorated based on nested-application,
but in cases where nested-application is unknown, use application
field to decorate.
Also, do not close tcp session after every syslog message

Change-Id: I2129b0335e5fd8b4d3ea442ab882ca49b8d9b29e
Partial-Bug: #1650353

rombie/contrail-controller,rombie/contrail-controller,rombie/contrail-controller,eonpatapon/contrail-controller,eonpatapon/contrail-controller,nischalsheth/contrail-controller,nischalsheth/contrail-controller,eonpatapon/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,eonpatapon/contrail-controller,eonpatapon/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,nischalsheth/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,eonpatapon/contrail-controller,eonpatapon/contrail-controller,nischalsheth/contrail-controller