IF update - 17: adding interface create/remove handler

Added support for #logical-interface #create / #remove #handler in IF module. On #row-status #change for interfaces in IF module will #call this #handler for #perform ing the #support #procedure s in the respective module. The interface #handler has been #register ed from the #GMPLS module to complete the interface create/remove sequence for MPLS-interface s. The existing interface activation handler in IF module has been updated to use the newly added interface call-back routine.

#IF update 17 + #GMPLS update 12 ...
[commit 43ff119c1f494c3a74324b6851e0c62aba933fe8] (https://github.com/nes-repo/NES-Open-Switch/commit/43ff119c1f494c3a74324b6851e0c62aba933fe8)