style and legal improvements

In this patch:
* added the GPL full text as required by Fedora guidelines.
* standardized the Makefile to conform with commonly used patterns
* replaced tabs with spaces in spec file

Change-Id: I671c7d4a649b282770eb589dc10ca5d3c376907e
Signed-off-by: Yoav Kleinberger <ykleinbe@redhat.com>
Reviewed-on: http://gerrit.ovirt.org/31338