Added saveAsImage functionality to compare
Added saveAsImage functionality to compare

jeremypoulter/emoncms,emoncms/emoncms,emoncms/emoncms,emoncms/emoncms,thaipowertech/emoncms,jeremypoulter/emoncms,chaveiro/emoncms,thaipowertech/emoncms,inverse/emoncms,thaipowertech/emoncms,emoncms/emoncms,jeremypoulter/emoncms,chaveiro/emoncms,inverse/emoncms,jeremypoulter/emoncms,thaipowertech/emoncms,inverse/emoncms,emoncms/emoncms,inverse/emoncms,chaveiro/emoncms,chaveiro/emoncms