Randomize tmp folder
Use http-https module instead of always sniffing
Fetch doc separately from changes

This accomplishes two things.

First, the changes feed isn't so huge to download.

Second, it allows us to get the _revisions data as well, so that our
new_edits=false PUT doesn't proliferate conflicts all over the place.

Preparation for the 'mcouch 2.0' style of doing things.
Pass around change objects instead of doc objects

Match the same pattern as mcouch 2.0 and npm-skim-registry 1.0.

Also, this avoids conflicts by passing through _revisions, and deletes
all conflicted leaf nodes when a DELETE change comes through the feed.
v1.0.0