(#81) - fixes for npm-fullfat-registry

Notable additions:

* startTime in db.info()
* multipart/related support for PUT
* changes with feed=continuous actually does
  a continuous feed like it's supposed to
0.5.2
(pouchdb/pouchdb#2546) - better error handling
0.5.3
(#85) - only use rawBodyParser where necessary

Also clean up the multiparty usage a bit.
Still doesn't replicate larger modules, but we're
getting there. May require a change in PouchDB
core so we don't have to read all the doc's attachments
into memory at once.
0.5.4
(#85) - actually implement multipart correctly

Just when I think I understand promises, something
like this comes along. This is probably the 5th time.
0.5.5
(#88) - make _changes actually continuous
0.5.6
(pouchdb/pouchdb#2545) - use bulk doc error if available