This commit involves the following changes:

Datapath:
  During lldp_send()
  foreach ISID-VLAN mapping set the ISID-VLAN Mapping status to 2 "Active"
  before sending it down the interface so the client receives accepted mappings.

Config:
1. Global - allow to get and set Auto-Attach status enabled/disabled
   See 'show configuration' and 'configure lldp aa-enable' ctl commands in lldpcli
2. Port  - Show some neighbor AA configuration (Element Type/VlAN/Sys MAC)
   Connect to a neighbor and use 'show neighbor' in lldpcli

Type lldpcli as root at a command prompt on the same machine as where the
lldpd is running to be able to see the new configuration changes.