Map openjdk-7-jre-headless to RHEL+SUSE

Provide package name mappings for openjdk-7-jre-headless:
        RHEL/Fedora: java-1.7.0-openjdk-headless
        SUSE: java-1_7_0-openjdk-headless

See https://review.openstack.org/#/c/86314

Change-Id: I3a351d0f9854f6f320ba145a71ffc66fd02c231c
Merge "Map openjdk-7-jre-headless to RHEL+SUSE"