Slightly more aggressive heuristic

[m3047]

The default heuristic now attenuates the base heuristic as well as the boost. Essentially this:

<base heuristic> + <boost> / <attenuator>

is changed to this:

(<base heuristic> + <boost>) / <attenuator>

Why? Would anyone in their right mind have CNAME chains seven or eight names deep? Well I can't speak to their state of mind but yes, yes they do. It's not a huge problem but the change should clear out some names which were only seen a handful of times some days ago.

[m3047]

Change is committed at 6e32b5e