Make it more clear in the README how exactly to build the docs

README.rst

@@ -9,7 +9,7 b' Welcome to IPython. Our full documentation is available on `our website'
 <http://ipython.org/documentation.html>`_; if you downloaded a built source
 distribution the ``docs/source`` directory contains the plaintext version of
 these manuals.  If you have Sphinx installed, you can build them by typing
-``make html`` for local browsing.
+``cd docs; make html`` for local browsing.
 
 
 Dependencies and supported Python versions
@@ -21,7 +21,7 b' functionality requires extra packages.'
 
 Officially, IPython requires Python version 2.6, 2.7, or 3.1 and above.
 
-    
+
 Instant running
 ===============