Ensure weights exist
Fix joinphrase

1. Joinphrase is on preceding item not on subsequent item.
2. Passing joinphrase through rather than using ';'.
Tweak artists

Remove unnecessary enumerate
Add rg title to rg node
Add tracknumber to metadata compare
Eliminate low-sources

Acoustid sources can be polluted by low-quality submissions.

So we find the maximum acoustid sources and eliminate any which have <
20% as many sources.