Fix VM's network model template for Power systems.

Setup the network model to 'spapr-vlan' by default in those old distro
vesions for new Power guests.

Also, setup the modern distro version for Power guests: RHEL7.0 and Fedora 19.

Signed-off-by: Paulo Vital <pvital@linux.vnet.ibm.com>
Fix test_osinfo.py to use new modern distro version dict.

Fix the testcase to use the new format of the modern distro version
dictionary.

In addition, fixed PEP8 issues and added this file to Makefile.am

Signed-off-by: Paulo Vital <pvital@linux.vnet.ibm.com>