pkgs/sage-conf/README.rst: Add links to source code

Author: Matthias Koeppe

pkgs/sage-conf/README.rst

@@ -22,8 +22,8 @@ sage_conf sdist on PyPI
 -----------------------
 
 This implementation of the ``sage_conf`` distribution package comes from
-https://trac.sagemath.org/ticket/29039, which adds the directory
-``pkgs/sage-conf_pypi/``.
+https://trac.sagemath.org/ticket/29039, which added the directory
+`pkgs/sage-conf_pypi <https://github.com/sagemath/sage/tree/develop/pkgs/sage-conf_pypi/>`_.
 
 To install, use ``pip install -v sage_conf``.  Using ``-v`` ensures that diagnostic
 messages are displayed.
@@ -77,8 +77,9 @@ sage_conf in the SageMath distribution
 
 The original version of the distribution package ``sage_conf`` is used
 internally in the SageMath distribution.  It is provided in the directory
-``pkgs/sage-conf/``.  This version of the package is generated
-by the Sage distribution's ``configure`` script.
+`pkgs/sage-conf <https://github.com/sagemath/sage/tree/develop/pkgs/sage-conf/>`_.
+This version of the package is generated by the Sage distribution's ``configure``
+script.
 
 
 sage_conf in downstream distributions
@@ -100,4 +101,4 @@ Upstream Contact
 https://www.sagemath.org
 
 This package is included in the source code of the Sage distribution,
-in ``pkgs/sage-conf*``.
+in `pkgs/sage-conf* <https://github.com/sagemath/sage/tree/develop/pkgs/>`_.