Change core = 8.x to backdrop = 1.x

Minor update to remain compatible after
https://github.com/backdrop/backdrop-issues/issues/117
adding xmlrpc-master.info to test installing from admin/modules/install
adding Drupal core = 7.x to test install from admin/modules/install
still testing install from admin/modules/install
still testing admin/modules/install
Merge pull request #2 from kreynen/master

Change core = 8.x to backdrop = 1.x