a 0.3.0 User is away.
c 17 IRC operator wants to receive connect/disconnect NOTICEs.
+ C 19 Only users that share a channel are allowed to send messages.
i 0.0.1 User is "invisible".
o 0.0.1 User is IRC operator.
r 0.0.1 User is restricted.
mode since description
b 0.5.0 Add/remove a host mask to the ban list.
+ e 19 Add/remove a host mask to the exception list.
i 0.5.0 Channel is "invite only".
I 0.5.0 Add/remove a host mask to the invite list.
k 0.6.0 Channel has a "key" (a password).
mode since description
+ q 20? User is channel owner can only be set by a service, other
+ owner and irc op. Can promote other users to q, a, o, h, v.
+ a 20? User is channel admin and can promote other users to v, h, o
o 0.2.0 User is channel operator and can op/kick/... other members.
+ h 20? User is half op and can set channel modes imntvIbek and kick
+ voiced and normal users.
v 0.2.0 User is "voiced" and can speak even if channel is moderated.