Change ordered list to use numbers.

Orderd list was using letters, but sphynx was numbering it. The block
after the list was using letters to refer to items in the list.

Make everything use numbers.

Author: rouilj

doc/customizing.txt

@@ -2266,27 +2266,27 @@ where tracker root is ``/tracker/`` or ``/cgi-bin/roundup.cgi/tracker/``
 We're looking at "issue", "issue1", "@@file/style.css", "file1" and
 "file1/kitten.png" in the cases above.
 
-a. with is no path we are in the "home" context. See `the "home"
+1. with is no path we are in the "home" context. See `the "home"
    context`_ below for details. "index" or "home" paths may also be used
    to switch into "home" context.
-b. for paths starting with "@@file" the additional path entry ("style.css"
+2. for paths starting with "@@file" the additional path entry ("style.css"
    in the example above) specifies the static file to be served
    from the tracker TEMPLATES directory (or STATIC_FILES, if configured).
    This is usually the tracker's "html" directory. Internally this works
    by raising SendStaticFile exception.
-c. if there is something in the path (as in example 1, "issue"), it
+3. if there is something in the path (as in example 1, "issue"), it
    identifies the tracker class to display.
-d. if the path is an item designator (as in examples 2 and 4, "issue1"
+4. if the path is an item designator (as in examples 2 and 4, "issue1"
    and "file1"), then we're to display a specific item.
    :ref:`Note. <strip_zeros>`
-e. if the path starts with an item designator and is longer than one
+5. if the path starts with an item designator and is longer than one
    entry (as in example 5, "file1/kitten.png"), then we're assumed to be
    handling an item of a ``FileClass``, and the extra path information
    gives the filename that the client is going to label the download
    with (i.e. "file1/kitten.png" is nicer to download than "file1").
    This raises a ``SendFile`` exception.
 
-Neither b. or e. use templates and stop before the template is
+Neither 2. or 5. use templates and stop before the template is
 determined. For other contexts the template used is specified by the
 ``@template`` variable, which defaults to: