bugs-bug-7873-pg_restore-clean-tries-to-drop-tables-that-don-t-exist (patch 1 of 1)

'git apply --summary --stat --apply --verbose' output was:

error: No changes

For original context, see http://www.postgresql.org/message-id/CAFj8pRCLmnA9B2ROnzmwjAjCBq--p-P_2Kq_21N21YX1Kdd8cA@mail.gmail.com
Adding travis.yml