Make use of yes/no booleans in playbooks

At the moment Ansible prefers yes/no for module booleans, however booleans in playbooks are still using True/False, rather than yes/no. This changes modifies boolean uses in playbooks (and man pages) to favor yes/no rather than True/False.

This change includes:

- Adaptation of documentation and examples to favor yes/no
- Modification to manpage output to favor yes/no (the docsite output already favors yes/no)

test/playbook-included.yml

@@ -1,7 +1,7 @@
 ---
 - hosts: all
   connection: local
-  gather_facts: False
+  gather_facts: no
   tasks:
   - action: debug msg="$variable"
 
@@ -9,6 +9,6 @@
   connection: local
   vars:
   - ugly: var
-  gather_facts: False
+  gather_facts: no
   tasks:
   - action: debug msg="$variable"