web disco : improved ResourceDownload, urls, cleanup
ResourceDownloadService (single Jersey client to avoid perfs pb,
   made address conf'ble, also plugged in guessApplicationName)
added config/easysoa.properties-based conf props in DocumentService
improved urls in custom ui by using it (in ftl, getters in Root
   (EasySOAModuleRoot), isDevModeSet, quick ref in wiki)
   & by computing dbb host util (using VirtualHostHelper from
   request else network)
& same for node instead of getNetworkIP
webengine cleanup (serialization (SoaNodeInformationFactory),
controller logging & warnings)