inst_upgrade_urls.rb client fixes

- remove old repositories (repo files) to avoid loading old
  SLE11 repositories when refreshing a registered service
  ([bnc#880971](https://bugzilla.novell.com/show_bug.cgi?id=880971))

- remove old services to get rid of the old NCC service

(Note: everything is backed up into `/var/adm/backup/upgrade/zypp`
directory)

- 3.1.88