Database.list support other-design-doc couch-9.4.13

Couch supports two types of API calls for lists
9.4.15.  /db/_design/design-doc/_list/list-name/view-name
[9.4.13.  /db/_design/design-doc/_list/list-name/other-design-doc/view-name][1]

This pull request adds support for the latter

[1]: http://docs.couchdb.org/en/latest/api/design.html#get-db-design-design-doc-list-list-name-other-design-doc-view-name