* src/dapi/DataApiFactory.js (_createDataApi): Add support for
`quote'.
* src/dapi/http/HttpDataApi.js (__construct): New `enctype' argument.
(_encodeData, _encodeKeys): Remove former, rename latter to former.
(encodeData, _urlEncode): Encode based on enctype and method.
(*): Strict mode, es6 style.