Fix markup in format.rst. (#193)

This ensures that

1) the various literal blocks are properly highlighted as rst or python
   depending on their contents,
2) the documentation for the Warnings and See Also sections does not
   appear as quote blocks.

Author: jnothman

doc/format.rst

@@ -119,6 +119,8 @@ The sections of a function's docstring are:
 
      """
 
+.. highlight:: rst
+
 2. **Deprecation warning**
 
    A section (use if applicable) to warn users that the object is deprecated.
@@ -276,46 +278,46 @@ The sections of a function's docstring are:
 
 10. **Warnings**
 
-   An optional section with cautions to the user in free text/reST.
+    An optional section with cautions to the user in free text/reST.
 
 11. **See Also**
 
-   An optional section used to refer to related code.  This section
-   can be very useful, but should be used judiciously.  The goal is to
-   direct users to other functions they may not be aware of, or have
-   easy means of discovering (by looking at the module docstring, for
-   example).  Routines whose docstrings further explain parameters
-   used by this function are good candidates.
+    An optional section used to refer to related code.  This section
+    can be very useful, but should be used judiciously.  The goal is to
+    direct users to other functions they may not be aware of, or have
+    easy means of discovering (by looking at the module docstring, for
+    example).  Routines whose docstrings further explain parameters
+    used by this function are good candidates.
 
-   As an example, for ``numpy.mean`` we would have::
+    As an example, for ``numpy.mean`` we would have::
 
-     See Also
-     --------
-     average : Weighted average
+      See Also
+      --------
+      average : Weighted average
 
-   When referring to functions in the same sub-module, no prefix is
-   needed, and the tree is searched upwards for a match.
+    When referring to functions in the same sub-module, no prefix is
+    needed, and the tree is searched upwards for a match.
 
-   Prefix functions from other sub-modules appropriately.  E.g.,
-   whilst documenting the ``random`` module, refer to a function in
-   ``fft`` by
+    Prefix functions from other sub-modules appropriately.  E.g.,
+    whilst documenting the ``random`` module, refer to a function in
+    ``fft`` by
 
-   ::
+    ::
 
-     fft.fft2 : 2-D fast discrete Fourier transform
+      fft.fft2 : 2-D fast discrete Fourier transform
 
-   When referring to an entirely different module::
+    When referring to an entirely different module::
 
-     scipy.random.norm : Random variates, PDFs, etc.
+      scipy.random.norm : Random variates, PDFs, etc.
 
-   Functions may be listed without descriptions, and this is
-   preferable if the functionality is clear from the function name::
+    Functions may be listed without descriptions, and this is
+    preferable if the functionality is clear from the function name::
 
-     See Also
-     --------
-     func_a : Function a with its description.
-     func_b, func_c_, func_d
-     func_e
+      See Also
+      --------
+      func_a : Function a with its description.
+      func_b, func_c_, func_d
+      func_e
 
 12. **Notes**
 
@@ -393,6 +395,8 @@ The sections of a function's docstring are:
         docstring, the table markup will be broken by numpydoc processing.  See
         `numpydoc issue #130 <https://github.com/numpy/numpydoc/issues/130>`_
 
+.. highlight:: pycon
+
 14. **Examples**
 
     An optional section for examples, using the `doctest
@@ -464,6 +468,7 @@ The sections of a function's docstring are:
     `matplotlib.sphinxext.plot_directive` is loaded as a Sphinx extension in
     ``conf.py``.
 
+.. highlight:: rst
 
 Documenting classes
 -------------------
@@ -501,7 +506,9 @@ In general, it is not necessary to list class methods.  Those that are
 not part of the public API have names that start with an underscore.
 In some cases, however, a class may have a great many methods, of
 which only a few are relevant (e.g., subclasses of ndarray).  Then, it
-becomes useful to have an additional **Methods** section::
+becomes useful to have an additional **Methods** section:
+
+.. code-block:: python
 
   class Photo(ndarray):
       """