qPingTool: migration to Plone 3

• Make it work in Plone 3
• Make ping tool and ping info objects zope3 schema based
• Enhance pings management for contexts
  • in each context user should be able to select which services to ping
• Check response after pings
  • aggregation services can have own requirements for the RSS and blog page formatting, this should be investigated and documented.
• Implement alternative urls for pings
  • we can host RSS on feedburner.com, so we need a way to point pingtool (and Plone) to publish the custom RSS feed URL.
• What else?