Having content negotiation with more than just JSON content
might follow REST principles.

All entities annotated with e.g. @XmlRootElement can be send as XML data.
This requires client to send Accept header with value "application/json"
to fetch JSON responses.
Default Accept header send by client is something like:
"text/html,application/xhtml+xml,application/xml"
which requests an XML document, not JSON document but JSON is expected.

This should enable annotation based cache-control header values.
Added a cache max age of 60 seconds to statistics resource. Proxy-Servers
should cache a statistics resource for about 60 seconds.

This will allow dynamic configuration depending on property file settings.

Removed connector client bean from XML based configuration and added bean
creation into JavaBased config class. Bean will be created if there is
a property "connector.enable" with value "true" otherwise no bean will
be created wich has the same behavior removing bean definition from XML
configuration file.

No need to change application config - can be done in property file :-)

Had to fix CouchDBDao.getSessionFromId() to implement working permission
evaluation.

This small method had thrown net.sf.json.JSONException wich causes
Spring to send HTTP 405 - Method not allowed and block request.

Spring security based permission check will do this for us.

Permission handling is the same as with removed Authorized annotation