Strip trailing whitespaces and normalize line endings

Trailing whitespace do not have impact on the result, they are just
unused bytes. Most text editors are configured to strip trailing
whitespaces. Remove them all in one go.

Update a handful of files to use the UNIX line ending.

doc/usage/restructuredtext/directives.rst

@@ -665,7 +665,7 @@ __ http://pygments.org/docs/lexers
    .. note::
 
       If you want to select only ``[second-section]`` of ini file like the
-      following, you can use ``:start-at: [second-section]`` and 
+      following, you can use ``:start-at: [second-section]`` and
       ``:end-before: [third-section]``:
 
       .. code-block:: ini
@@ -692,7 +692,7 @@ __ http://pygments.org/docs/lexers
              # [initialize]
              app.start(":8000")
              # [initialize]
-     
+
 
    When lines have been selected in any of the ways described above, the line
    numbers in ``emphasize-lines`` refer to those selected lines, counted