Single point for Crowd client configuration

Currently, there are two files which need to be edited for tweaking the Crowd client library: crowd.properties and crowd-ehcache.xml.

It would be good if there was a single file which users can edit to configure the Crowd client. This could be achieved by rolling in the cache configuration in to the crowd.properties file or by creating a single XML configuration.

Currently, users are unable to tweak the transport layer configuration, such as:

• Max size of connection pool
• GZip requests
• etc, see http://xfire.codehaus.org/HTTP+Transport for other possible parameters.

They should be configurable via the new properties/XML file.