only_if reference)
Signed-off-by: Brian Coca <briancoca+dev@gmail.com>

  Migrated all examples: in DOCUMENTATION=''' string to standalone EXAMPLES=''' string
  Added deprecation warning to moduledev.rst and remove deprecated example from it
  Fixed up a few typos and uppercased some acronyms.
  add consistency to how EXAMPLES are formatted

Both modules seboolean and zfs have not been adapted since they defer from the default (either by having a 'null' or special state, or prefering "on"/"off" for state indication.

This makes more sense as there is no purpose in running these remotely.

 - fixed template (it was the template), adding indentation with Jinja2
 - added description of code examples to man-page template (was missing)
 - fixed fireball, cron, and debug module examples to confrom

After helping someone on IRC he was interested to have this debug module in upstream. This module simply 'prints' a message, and can be ordered to fail if needed. It helps to troubleshoot or understand inventory/facts issues and/or experiment with statements and conditions using only_if.

Here is a small example playbook:

```yaml
- hosts: all
  tasks:
  - local_action: debug msg="System $inventory_hostname has uuid ${ansible_product_uuid}"
  - local_action: debug msg="System $inventory_hostname lacks a gateway" fail=yes
    only_if: "is_unset('$ansible_default_ipv4.gateway')"
  - local_action: debug msg="System $inventory_hostname has gateway ${ansible_default_ipv4.gateway}"
    only_if: "is_set('$ansible_default_ipv4.gateway')"
```

outputting:
```
[root@moria ansible]# ansible-playbook -v -l localhost:x220 test6.yml

PLAY [all] *********************

GATHERING FACTS *********************
ok: [localhost]
ok: [x220]

TASK: [debug msg="System $inventory_hostname has uuid $ansible_product_uuid"] *********************
ok: [localhost] => {"msg": "System localhost has uuid d125a48c-364f-4e65-b225-fed42ed61fac"}
ok: [x220] => {"msg": "System x220 has uuid d125a48c-364f-4e65-b225-fed42ed61fac"}

TASK: [debug msg="System $inventory_hostname lacks a gateway" fail=yes] *********************
failed: [localhost] => {"failed": true, "msg": "System localhost lacks a gateway", "rc": 1}
ok: [x220] => {"msg": "System x220 has gateway 192.168.1.1"}

PLAY RECAP *********************
localhost                      : ok=2    changed=0    unreachable=0    failed=1
x220                           : ok=3    changed=0    unreachable=0    failed=0

```

I had some other plans for the module, like displaying host inventory and complete inventory to help understand inventory and facts modules, but that would require an action-plugin for transfering inventory information etc... And I am not sure this is wanted/best done in a module.