modules/autoop.cpp & autovoice.cpp: Be more gender neutral.

Many people, myself included, feel like the word "guy" means masculine
people this way excluding feminine people. This is a small change, but
this can make some ZNC users a little happier.

It seems that this commit does more than I intended, but that is caused
by one or more of the following things:

* my vimrc converts tabs to spaces.
* my vimrc converts DOS line endings to UNIX line endings.
* my gitconfig prefers UNIX line endings.