Vultr: Introducing vr_region_facts module (#42471)

This commit introduces a new module called vr_region_facts.

This module aims to return the list of region avaiable avaiable to use
where boot servers.

Sample available here:

```
"vultr_region_facts": [
    {
      "block_storage": false,
      "continent": "Europe",
      "country": "FR",
      "ddos_protection": true,
      "id": 24,
      "name": "Paris",
      "regioncode": "CDG",
      "state": ""
     }
  ]
```

test/legacy/roles/vr_region_facts/tasks/main.yml

@@ -0,0 +1,19 @@
+# Copyright (c) 2018, Yanis Guenane <yanis+ansible@guenane.org>
+# GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
+---
+- name: test gather vultr region facts in check mode
+  vr_region_facts:
+  check_mode: yes
+
+- name: verify test gather vultr region facts in check mode
+  assert:
+    that:
+    - ansible_facts.vultr_region_facts|selectattr('name','equalto','Atlanta') | list | count == 1
+
+- name: test gather vultr region facts
+  vr_region_facts:
+
+- name: verify test gather vultr region facts
+  assert:
+    that:
+    - ansible_facts.vultr_region_facts|selectattr('name','equalto','Atlanta') | list | count == 1

test/legacy/vultr.yml

@@ -6,12 +6,13 @@
   connection: local
   roles:
     - { role: vr_account_facts, tags: test_vr_account_facts }
-    - { role: vr_user, tags: test_vr_user }
-    - { role: vr_ssh_key, tags: test_vr_ssh_key }
-    - { role: vr_ssh_key_facts, tags: test_vr_ssh_key_facts }
-    - { role: vr_firewall_group, tags: test_vr_firewall_group }
-    - { role: vr_firewall_rule, tags: test_vr_firewall_rule }
-    - { role: vr_startup_script, tags: test_vr_startup_script }
     - { role: vr_dns_domain, tags: test_vr_dns_domain }
     - { role: vr_dns_record, tags: test_vr_dns_record }
+    - { role: vr_firewall_group, tags: test_vr_firewall_group }
+    - { role: vr_firewall_rule, tags: test_vr_firewall_rule }
+    - { role: vr_region_facts, tags: test_vr_region_facts }
     - { role: vr_server, tags: test_vr_server }
+    - { role: vr_ssh_key, tags: test_vr_ssh_key }
+    - { role: vr_ssh_key_facts, tags: test_vr_ssh_key_facts }
+    - { role: vr_startup_script, tags: test_vr_startup_script }
+    - { role: vr_user, tags: test_vr_user }