Restructure virt-backup-restore-overview.adoc to move 'Additional resources' to the end of the file, after the include statements.

Line 1: Assign [role="_abstract"] to a paragraph to use it as  <shortdesc> in DITA. 

See https://docs.google.com/spreadsheets/d/1vLrFYdKphcFLoWNEH3E4oCJ2HsOUDLQ72yFnfiYNnXU/edit?gid=503904153#gid=503904153