Update README.rst

Author: bnmnetp

README.rst

@@ -17,6 +17,13 @@ If you are completely new to pip and github text editors, I have written a more
 
     pip install runestone
 
+On some versions of pip that will fail and you need to use:
+
+::
+
+    pip install --pre runestone
+
+
 
 Or, if you prefer to live on the development edge, you can check out the very latest from:
 
@@ -69,4 +76,4 @@ If you already have an existing `Sphinx <http://sphinx-doc.org>`_  project and y
 * Then modify your html_static_path:  ``html_static_path = ['_static']  + runestone_static_dirs()``  Again you may have your own set of static paths in the initial list.
 
 
-See https://github.com/bnmnetp/runestone/wiki/DevelopmentRoadmap to get a sense for how this is all going to come together.
+See https://github.com/bnmnetp/runestone/wiki/DevelopmentRoadmap to get a sense for how this is all going to come together.