Fix closing of Changes feed

This release fixes a bug that closing the Changes feed could block, potentially indefinitely, if Next() was waiting in a separate goroutine.

Tests are also now run against Go 1.13.

The long-awaited stable release of Kivik 2!

Merge pull request #216 from go-kivik/closeChanges

Fix closing of an iterator while a Next() is in progress

Minor cleanups

This release is expected to be the final release before tagging v2.0.0 as stable. This is release contains mostly internal cleanups, but with one external change: It now includes the Content-Encoding header value for attachments.

v2.0.0-pre3: Merge pull request #197 from jspspike/master

Added  to list of params to be JSON encoded

v2.0.0-pre2: Merge pull request #194 from go-kivik/docfmt

Fix doc formatting, and add NoMultpartGet details

2.0.0 pre-release

Merge pull request #180 from go-kivik/respErr

Improve errors

CouchDB 2.2.0 & Go 1.11 support

Merge pull request #110 from go-kivik/stable1-couch22

Run tests against CouchDB 2.2

Add cluster config support for CouchDB 2.1 compatibility

Merge pull request #86 from go-kivik/clusterStats1.x

Support reading of cluster stats and full response from DB stats

Test improvements

No functional changes

Update tests to work with Go 1.10

Test changes only, no functional changes.