(#928) - Remove non working submit tests, add notification of tests complete
(#926) - HTTP Basic Auth for Userinfo in the url.

Before, HTTP Basic Authorization header was set only when user/password
were passed in the opts object for the instantiation of PouchDB, now
http://user:password@host works also.
(#789) - Count pending revisions in a correct way

When multiple conflicting revisions for some id were present on a remote
database, `pending` variable was incremented only by one to account for
the document itself, but it was then decremented for every conflicting
change. This effected in negative `pending` value, which in turn meant
that `completed` callback was never called (due to `pending === 0` being
false).

This change modifies semantic of `pending` variable to count revisions
to process instead of documents. Calculation of `docs_read` was changed
as well, because it should include all fetched documents, including
conflicting revisions - until now it was counting something else than
`docs_written`, so a situation when `docs_written !== docs_read` was
possible (which should not happen, in general, `docs_read ===
docs_written + docs_write_failures`).
(#939, #935) Change way of calculating revsDiff

Until now, `revsDiff` was using `rev_info` option to `get` routine as a
source of information for which revisions are present and which are
missing. This led to problems, as purpose of `rev_info` is to list
revision history of current winning revision, so it doesn't include any
information about conflicts or deleted revisions.

CouchDB itself is using internal index information for obtaining state
of revisions for a given document (see
https://github.com/apache/couchdb/blob/master/src/couchdb/couch_db.erl#L193),
so it seems valid to do the same in PouchDB, by traversing the whole
revision tree obtained by using custom (internal) API. HTTP adapter
overrides `revsDiff` to use a POST request, so it works fine.