Avatar spellbooks

[Enea]

Some of the less-run areas on Lyme now randomly pop spell/song/skill books for avatar-level spells, skills, and songs. I'll be adding non-avatar books to the other continents in the coming weeks, as well as adding books for <21st level spells/skills/songs to the less-run VK areas.

Not all of the books will pop this way. The ones that already have decent pop rates are not on the random-pop lists.