add null check for getLinkInfo return value

so the user does not have to check floodlight logs for them.

[BVS-486] getPortType will default to UPLINK ports for BigSwitchOVS.  The autoportfast detection is performed only in BSNOVS and Xenon switches.

* alwasy log stack trace at debug level (even if we just log the message
  at error)
* don't wrap other exceptions in SwitchStateException. We don't log that
  with stack trace
* IOFSwitch.setDebugCounterService now throws the correct exception

add fields to forwardingconfig model in bigcon to hold idle/hard timeouts
add storage listeners for these 2 columns in bigfloodlight's forwarding

Flattened debug counters REST output a little bit.

moving counter registration to init() methods, and use of metadata constants

 - flushNow is a property of the update instead of the event
 - event timestamp is displayed in ISO8601 style
 - event registry returns an event updater object instead of the eventId
 - event update is done with a user defined object which is accessed via reflection and annotations
 - metadata is expressed using varargs and metadata string constants
 - changed unit tests

Update CLI to decode vendor action data as keys in the vendor data json dictionary