Merge branch 'ServerMode'

* ServerMode:
  Handle channel user modes 'a', 'h', and 'q' from remote servers
  Handle unknown channel modes on server links
  Handle unknown user modes on server links
  IRC_MODE(), Client_Mode(): code cleanup [2/2]
  Enlarge client user mode buffer, reduce client flags buffer
  Infom clients when other servers change their user modes
  IRC_MODE(), Client_Mode(): code cleanup [1/2]