MobiTool

The point:
I was given a kindle, I got some books, some had bad punctuation
and spelling mistakes, or the OCR had just gotten it wrong.

I wrote this so I could fix them, but that purpose got waylaid
when I was bored.

What it does:

- Opens and displays mobi documents encoded with PalmDoc compression
- Extract/replace images and text
- Modify some basic information (title, author, blurb, cover images)

What it doesn't (but may do in future), or what's broken:

- Compress with PalmDoc (the unit test succeeds, but kindle doesn't
  display correctly in places)
- Generate mobi table of contents for imported text
- Decode/generate INDX and TAGX records