Refactor OpenStack security group creation
Refactor OpenStack security group creation

* Adds new openstack-security-groups role
* Addresses Issue #211 and adds all instances to default group
* Defines default security group variable with all groups/rules
* Sets security group variables per type (master,node,nfs,dns)
* Supports specifying no security group for a type (e.g. nfs)
* Uses new Ansible 2.x modules

scollier/openshift-ansible-contrib,glennswest/openshift-ansible-contrib,openshift/openshift-ansible-contrib,dav1x/openshift-ansible-contrib,cooktheryan/openshift-ansible-contrib,dav1x/openshift-ansible-contrib,cwilkers/openshift-ansible-contrib,pschiffe/openshift-ansible-contrib,scollier/openshift-ansible-contrib,openshift/openshift-ansible-contrib,openshift/openshift-ansible-contrib,pschiffe/openshift-ansible-contrib,dav1x/openshift-ansible-contrib,scollier/openshift-ansible-contrib,cooktheryan/openshift-ansible-contrib,dav1x/openshift-ansible-contrib,pschiffe/openshift-ansible-contrib,scollier/openshift-ansible-contrib,Tlacenka/openshift-ansible-contrib,cwilkers/openshift-ansible-contrib,cooktheryan/openshift-ansible-contrib,openshift/openshift-ansible-contrib,cwilkers/openshift-ansible-contrib,Tlacenka/openshift-ansible-contrib,pschiffe/openshift-ansible-contrib,Tlacenka/openshift-ansible-contrib,cwilkers/openshift-ansible-contrib,Tlacenka/openshift-ansible-contrib,cooktheryan/openshift-ansible-contrib