Added search function (unfortunately very slow)

Changelog:

Added a very slow and data-intensive search function. The search will be VERY slow, and may make some browsers crash - because of the way GitHub Pages works, the only way to search the archive it is to just download the whole thing at once. If your browser can’t handle it, or you’re on a metered data plan, I’d STRONGLY suggest that you just download the ebook and search that instead.
Renamed the ebook link, because some people were having trouble understanding it what it was.
Updated the list of currently-incomplete transcripts and added it to the top of the page, for those who have been volunteering to help transcribe.
Moved some other menu links down to the bottom of the page (it was getting crowded up there).
Fixed typos and added editable Google Doc for official transcript MAG072, which I hate.

Please email me if you run into any problems!