update indigo

* submodules/indigo e20dbd1...83687ba (1):
  > Merge into master from pull request #105: OFStateManager debug counters (https://github.com/floodlight/indigo/pull/105)
update loxigen-artifacts

* submodules/loxigen-artifacts f6438ee...9138196 (1):
  > Artifacts from https://github.com/floodlight/loxigen/compare/01cfbb25743fc99588520a299e1eb882265aa2e1...1bc22f26bd88dae76dc749137998c16864718d5d
ivs: link in debug_counter module
Merge into master from pull request #131:
update submodules (https://github.com/floodlight/ivs/pull/131)