Set the default LANG to en_US.UTF-8 and also set LC_CTYPE

Fixes #6737

lib/ansible/constants.py

@@ -108,7 +108,7 @@ DEFAULT_MODULE_NAME       = get_config(p, DEFAULTS, 'module_name',      None,
 DEFAULT_PATTERN           = get_config(p, DEFAULTS, 'pattern',          None,                       '*')
 DEFAULT_FORKS             = get_config(p, DEFAULTS, 'forks',            'ANSIBLE_FORKS',            5, integer=True)
 DEFAULT_MODULE_ARGS       = get_config(p, DEFAULTS, 'module_args',      'ANSIBLE_MODULE_ARGS',      '')
-DEFAULT_MODULE_LANG       = get_config(p, DEFAULTS, 'module_lang',      'ANSIBLE_MODULE_LANG',      'C')
+DEFAULT_MODULE_LANG       = get_config(p, DEFAULTS, 'module_lang',      'ANSIBLE_MODULE_LANG',      'en_US.UTF-8')
 DEFAULT_TIMEOUT           = get_config(p, DEFAULTS, 'timeout',          'ANSIBLE_TIMEOUT',          10, integer=True)
 DEFAULT_POLL_INTERVAL     = get_config(p, DEFAULTS, 'poll_interval',    'ANSIBLE_POLL_INTERVAL',    15, integer=True)
 DEFAULT_REMOTE_USER       = get_config(p, DEFAULTS, 'remote_user',      'ANSIBLE_REMOTE_USER',      active_user)

lib/ansible/module_utils/basic.py

@@ -192,6 +192,7 @@ class AnsibleModule(object):
                     self.argument_spec[k] = v
 
         os.environ['LANG'] = MODULE_LANG
+        os.environ['LC_CTYPE'] = MODULE_LANG
         (self.params, self.args) = self._load_params()
 
         self._legal_inputs = ['CHECKMODE', 'NO_LOG']