Add HA option, change to yaml inventory, cleanup

- HA option for multiple server nodes using embedded etcd
- Switch to yaml inventory file for easier editing and combining vars
- Update to full ansible module names
- Change master/node names to server/agent
- Cleanup small linting errors
- Add reboot playbook which staggers reboot to keep HA cluster up
- Move playbooks to playbook directory

Signed-off-by: Derek Nola <derek.nola@suse.com>

roles/prereq/tasks/main.yml

@@ -9,14 +9,14 @@
     name: net.ipv4.ip_forward
     value: "1"
     state: present
-    reload: yes
+    reload: true
 
 - name: Enable IPv6 forwarding
   ansible.posix.sysctl:
     name: net.ipv6.conf.all.forwarding
     value: "1"
     state: present
-    reload: yes
+    reload: true
   when: ansible_all_ipv6_addresses
 
 - name: Add br_netfilter to /etc/modules-load.d/
@@ -37,7 +37,7 @@
     name: "{{ item }}"
     value: "1"
     state: present
-    reload: yes
+    reload: true
   when: ansible_distribution in ['CentOS', 'Red Hat Enterprise Linux','RedHat']
   loop:
     - net.bridge.bridge-nf-call-iptables