webadmin: add dash - before items in confirmation pop up

 Chagning the the DefaultConfirmationPopupView to add dash (-)
before every item in the pop for consistency purpose.

Change-Id: Ib09a5ca23e81e2c11e64e08084691ebc03e2f602
Signed-off-by: Ramesh Nachimuthu <rnachimu@redhat.com>