bump hm_next

cf-release/src/health_manager_next
    git shortlog a4715b168dc1f246af6f9093cf77e8364f322c5f..814638a38688bc7c22efba17a2d8e0a4d70c88b8
        Bob Nugmanov (6):
              use yajl everywhere
              Merge "use yajl everywhere"
              update vcap-common
              bump steno gem
              varz: missing_instances
              fix: do not publish expected vitals in case of error

Change-Id: I8fd10354b9a6d81415d7a0f8970de8781ab40fd8
Merge "bump hm_next"