Description: A control object to activate/deactivate
ceSensorExtThresholdNotification.

This object should hold any of the below values.
enabled(1)    - The notification is enabled for this entity
disabled(2)   - The notification is disabled for this entity
transparent(3)- The notification is enabled/disabled based on
                ceSensorExtThresholdNotifGlobalEnable
                object

This object controls generation of
ceSensorExtThresholdNotification for this threshold.
An exception to this is, if this object is set to 'transparent'
then ceSensorExtThresholdNotification for this threshold
is controlled by ceSensorExtThresholdNotifGlobalEnable
object.

This truth table explains how
ceSensorExtThresholdNotifEnable is related with 
ceSensorExtThresholdNotifGlobalEnable to control the
ceSensorExtThresholdNotification for this threshold

E = enabled, D = Disabled, T = Transparent
local_flag =  ceSensorExtThresholdNotifEnable
global_flag = ceSensorExtThresholdNotifGlobalEnable

local_flag  global_flag   outcome_per_interface
---------------------------------------------
   E            E            E
   E            D            D
   D            E            D
   D            D            D
   T            E            E
   T            D            D