Rename index.page spec.page

The page ID was already spec, and this is less confusing with the
home page of the regular help docs
[endlessm/eos-shell#4154]
REMOVEME write all the html visited in yelp to a file

Useful for debugging whats actually going on in yelp

Feel free to pop this commit off if all the html pages its writing
to disk gets annoying
[endlessm/eos-shell#4154]