Rename many bad things.

- Renames irc.Mask to irc.Host because that's what it actually is.
- Renames irc.WildMask to irc.Mask because that's what it actually is.
- Ripples Go's property naming scheme throughout many types (Setter has
  SetProperty and the getter is only Property)
- Abstracts out the Host parsing bits so that they can be used directly
  from the irc package while allowing irc.Message to be built out later.

List of renames:
- Rename irc.Mask -> irc.Host
- Rename irc.WildMask -> irc.Mask
- Rename irc.Host.GetNick -> irc.Host.Nick
- Rename irc.Host.GetUsername -> irc.Host.Username
- Rename irc.Host.GetHost -> irc.Host.Hostname
- Rename irc.Host.GetFullhost -> irc.Host.String
- Rename data.User.GetRealname -> data.User.Realname
- Rename data.User.Realname -> data.User.SetRealname
- Rename data.Channel.GetBans -> Bans
- Rename data.Channel.Bans -> SetBans
- Rename data.Channel.GetName -> data.Channel.Name
- Rename data.Channel.Topic -> data.Channel.SetTopic
- Rename data.Channel.GetTopic -> data.Channel.Topic
Add nice helpers and a timestamp to irc.Message

- Create a NewMessage function to create the irc.Message with the
  current timestamp.
- Add mirror methods of the irc.Host for the Sender of irc.Message. This
  makes it more obvious that it's the definitive go-to for this
  information. Rather than relying on the prescence of a User object in
  the CommandData.
- Remove connMessage and discMessage. Nice as they were being constants,
  they need to now come with fresh timestamps.
- Fix simple.go to compile again with the new nice changes.