[maven-release-plugin] prepare for next development iteration
Implement XML writer.
Add stub implementation for XML reader.
Add documentation.
Do not write empty maps and lists.
Fix JSON to XML converting.
Fix line length in output and DTD URI.
[maven-release-plugin] prepare release server-0.2.13
Merge tag 'server-0.2.13' into stable

[maven-release-plugin]  copy for tag server-0.2.13