fixups after review by jonas


ndb/src/mgmclient/CommandInterpreter.cpp:
  Guard the print mutex when running SHOW
ndb/src/mgmsrv/MgmtSrvr.cpp:
  replace global_flag_send_heartbeat_now with forceHB()/updateStatus()
  
  don't use bitmask as parameter to forceHB to reflect reality of what the
  function does.
  
  remove get_connected_ndb_nodes() as it is no longer used
ndb/src/mgmsrv/MgmtSrvr.hpp:
  remove unused get_connected_ndb_nodes()
  
  update updateStatus prototype
ndb/src/mgmsrv/Services.cpp:
  use new prototype for updateStatus() - doesn't accept NodeBitmask
ndb/src/ndbapi/ClusterMgr.cpp:
  remove global_flag_send_heartbeat_now, replace with forceHB.
  
  compute bitmask of nodes to send HB to in forceHB
ndb/src/ndbapi/ClusterMgr.hpp:
  update prototype for forceHB, don't give the illusion that NodeBitmask means much.