This is yukky but it works. Note: I had to duplicate the standard pix icon template
inside the font-awesome one because the way this is rendered does not support partials.
For font awesome icons I had only supported one of alt/title. This was because (subjectively) we have
done a terrible job of providing meaningful alt text for icons. This is not a good idea and not backwards
compatible so I have put it back again.
Fingers crossed I did not break 1000 behats.