Send oplevels correctly during a burst.

Send oplevels correctly during a burst.

src/hash.c (AddChannelUser): Initialize oplevel to the maximum, not -1.
src/proto-p10.c (parse_oplevel): Move up for easier inlining.
  (modeNode_sort): New function.
  (irc_burst): Use it to sort the membership list for channels so the
    members' oplevels can be sent correctly.
  (cmd_burst): Simplify the handling of oplevels.
  (mod_chanmode_parse): Only change the member's oplevel when opping or
    deopping -- otherwise +v would set it to MAXOPLEVEL!