Functionality for catching WHOIS results and calling passed function aliases
with the resulting account information that was divined from it, in the form
of the actual IRCEvent, the target
IRCUser within it, the user's account field, or merely
alone as an arity-0 function.
The section of kameloso.plugins.common that involves mixins.
This was all in one plugins/common.d file that just grew too big.