travis: update test for package verification

Use two separate repositories for pungi-gather testing and lorax
testing. One contains (unsigned) package downloaded by pungi-gather
only, and the other - by lorax only.

conf/travis-iso-unsigned2.ks

@@ -1,4 +1,4 @@
 %include travis-iso.ks
 
 # unsigned package to be downladed by lorax
-repo --name=unsigned --gpgkey=file:///tmp/qubes-installer/qubes-release/RPM-GPG-KEY-qubes-3.1-primary --baseurl=http://ftp.qubes-os.org/~marmarek/repo-verify-unsigned --ignoregroups=true
+repo --name=unsigned2 --gpgkey=file:///tmp/qubes-installer/qubes-release/RPM-GPG-KEY-qubes-3.1-primary --baseurl=http://ftp.qubes-os.org/~marmarek/repo-verify-unsigned2 --ignoregroups=true