Add hook for installing disk
Add hook for installing disk

This will be used by pre.sh and getinstalldisk
to direct the install.

xcat2/confluent,jjohnson42/confluent,jjohnson42/confluent,xcat2/confluent,jjohnson42/confluent,xcat2/confluent,xcat2/confluent,jjohnson42/confluent,jjohnson42/confluent,xcat2/confluent