Changes to convert to unicode at the borders

The module docs and vault changes solve issues where tracebacks can
happen.  The galaxy changes are mostly refactoring to be more pythonic
with a small chance that a unicode traceback could have occurred there
without the changes.  The change in __init__.py when we actually call
the pager makes things more robust but could hide places where we had
bytes coming in already so I didn't want to change that without auditing
where the text was coming from.

Fixes #14178

lib/ansible/utils/module_docs.py

@@ -24,7 +24,7 @@ __metaclass__ = type
 import os
 import sys
 import ast
-import yaml
+from ansible.parsing.yaml.loader import AnsibleLoader
 import traceback
 
 from collections import MutableMapping, MutableSet, MutableSequence
@@ -71,7 +71,7 @@ def get_docstring(filename, verbose=False):
                         continue
 
                     if 'DOCUMENTATION' in theid:
-                        doc = yaml.safe_load(child.value.s)
+                        doc = AnsibleLoader(child.value.s, file_name=filename).get_single_data()
                         fragments = doc.get('extends_documentation_fragment', [])
 
                         if isinstance(fragments, basestring):
@@ -91,7 +91,7 @@ def get_docstring(filename, verbose=False):
                             assert fragment_class is not None
 
                             fragment_yaml = getattr(fragment_class, fragment_var, '{}')
-                            fragment = yaml.safe_load(fragment_yaml)
+                            fragment = AnsibleLoader(fragment_yaml, file_name=filename).get_single_data()
 
                             if fragment.has_key('notes'):
                                 notes = fragment.pop('notes')