Fix spelling mistakes (comments only) (#25564)

Original Author : klemens <ka7@github.com>

Taking over previous PR as per
https://github.com/ansible/ansible/pull/23644#issuecomment-307334525

Signed-off-by: Abhijeet Kasurde <akasurde@redhat.com>

lib/ansible/utils/module_docs_fragments/fortios.py

@@ -63,5 +63,5 @@ options:
   backup_filename:
     description:
       - Specifies the backup filename. If omitted filename will be
-        formated like HOST_config.YYYY-MM-DD@HH:MM:SS
+        formatted like HOST_config.YYYY-MM-DD@HH:MM:SS
 """

lib/ansible/utils/module_docs_fragments/tower.py

@@ -19,7 +19,7 @@
 
 class ModuleDocFragment(object):
 
-    # Ansible Tower documention fragment
+    # Ansible Tower documentation fragment
     DOCUMENTATION = '''
 options:
     tower_host:

lib/ansible/utils/vars.py

@@ -154,7 +154,7 @@ def load_options_vars(options, version):
 def isidentifier(ident):
     """
     Determines, if string is valid Python identifier using the ast module.
-    Orignally posted at: http://stackoverflow.com/a/29586366
+    Originally posted at: http://stackoverflow.com/a/29586366
     """
 
     if not isinstance(ident, string_types):