Reorganized and clarrified the Holland backup-set config docs.

Re-arranged a few paragraphs to flow better, reworded things that
didn't make as much sense, provided better examples of the hooks.
I noticed this as well (actually similar rhetoric is also used in regards to the providers path). I was already thinking about removing it (I think it only exists for cases where folks are patching Holland, but if they are, they should know what's going on already). I'll make those corrections.