Restructure options / libraw in docs.

[SamWhited]

The options list is getting rather long. Maybe we should split the libraw structs out into their own doc file, and start dividing the options up by section (eg. interpolation options, color options, etc.).

[SamWhited]

Now that libraw is split out into a separate namespace the docs are somewhat readable again. Sections for various options may still be something we want to do, but it can come later.

As this is no longer really an issue, I'm closing it.