Import <= 1.7 configs

Adds compatibility bits for pre 2.0 releases.

Due to human error, there is a manual step necessary to fully import pre 2.0 build configs. If the Jenkins migrate old data page at administrativeMonitor/OldData/manage shows the error ConversionException: Cannot construct com.waytta.clientinterface.BasicClient then delete the <clientInterface> line from the config. This can be done with:
sed -i'.bak' '/<clientInterface>.*<\/clientInterface>/d' jenkinshome/jobs/jobname/config.xml

At this point reloading configs should restore the job data.