Renormalize dex scores to 1-100 scale

[stuartpb]

I picked 0-30 because that seemed analogous to D&D, but, honestly, now that I've got 99 projects, I think I'd rather have the granularity along integers afforded by 1 to 100. (I'm going to reserve 0 because non-positive dex scores are currently under consideration as a semantic signal: #10)