Fix a few editorial problems found:
* Use git.openstack.org instead of github.com since git.openstack.org is
the reference for OpenStack.
* Fix reference to repos, some used stackforge instead of openstack
namespace.
* Fix spelling of OpenStack.
* Remove mention of puppet-openstack module, it does not exist anymore.
Change-Id: Id1c24f53dce396931236e178565bc11daa9949ea
Update the cookiecutter templates to reflect various changes :
* Move to openstack/ scope
* More up to date metadata.json (operatingsystem_support)
* Fix white space
* Fix README naming and links
* Remove duplicated CHANGELOG
Change-Id: I520d60952f93a226a318465ec79567662274efde