support for couchdb installed in a subdirectory

[ktmud]

so code as:

 new(cradle.Connection)('http://living-room.com/couch', 80, {
      cache: true,
      raw: false
  });

and:

 new(cradle.Connection)('https://house.tld/living-room/couch/',  443, {
      cache: true,
      raw: false
  });

will work.

[panuhorsmalahti]

Lets try to get #284 merged.