Correct minor underline build complaints (#219)

* Correct minor underline build complaints

* Correct minor underline build complaints, additional file

Author: HayesJohnD

context_managers.rst

@@ -36,7 +36,7 @@ Let's see how we can implement our own Context Manager. This should allow
 us to understand exactly what's going on behind the scenes.
 
 Implementing a Context Manager as a Class:
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 At the very least a context manager has an ``__enter__`` and
 ``__exit__`` method defined. Let's make our own file-opening Context

decorators.rst

@@ -273,7 +273,7 @@ Now let's take a look at the areas where decorators really shine and
 their usage makes something really easy to manage.
 
 Authorization
-~~~~~~~~~~~~
+~~~~~~~~~~~~~
 
 Decorators can help to check whether someone is authorized to use an
 endpoint in a web application. They are extensively used in Flask web
@@ -296,7 +296,7 @@ authentication:
         return decorated
 
 Logging
-~~~~~~~~~~~~
+~~~~~~~
 
 Logging is another area where the decorators shine. Here is an example:
 

for_-_else.rst

@@ -1,5 +1,5 @@
 ``for/else``
-----------
+------------
 
 Loops are an integral part of any language. Likewise ``for`` loops are
 an important part of Python. However there are a few things which most
@@ -22,7 +22,7 @@ That is the very basic structure of a ``for`` loop. Now let's move on to
 some of the lesser known features of ``for`` loops in Python.
 
 ``else`` Clause
-^^^^^^^^^^^^^^^^^^^^
+^^^^^^^^^^^^^^^
 
 ``for`` loops also have an ``else`` clause which most of us are unfamiliar
 with. The ``else`` clause executes after the loop completes normally.