Eliminate redundancy (magic sections)

[oddhack]

The "Magical Spells and Scrolls" section (8.2) is largely reproducing information in the "SPELLS" section (6.10). Just moving the one or two columns worth of information into 6.10 would allow deleting this huge table.

Some of the spell information (esp. "Difficulty") is in the skill database and shouldn't be needed here - especially because it can change from campaign to campaign, in principle.