Add many more core commands.

- Make dispatchResultCheck tests use their constants for more robust
  testing.
- Change the API for Mask and WildMask to be more consistent, and less
  verbose. Now uses regular expressions.
- Make Store.RemoveUser return whether or not it actually did anything.
- Add a Store.LogoutByUsername to enable user names to be logged out.
- Add UserAccess.SetPassword to allow setting the password later.
- Add return parameter to UserAccess.AddMasks and UserAccess.DelMasks.
- Fix a bug where Commander was sending the wrong errors on host fail.
- Make Commander's AuthedCommands require authentication even if the
  command has no priveleges required.
- Add a better test to test ProtoCaps.Clone.