Added README to explain how to build the documentation.

doc/README

@@ -0,0 +1,49 @@
+How to build psycopg documentation
+----------------------------------
+
+- Install Sphinx, maybe in a virtualenv. Tested with Sphinx 0.6.4::
+
+    ~$ virtualenv pd
+    New python executable in pd/bin/python
+    Installing setuptools............done.
+    ~$ cd pd
+    ~/pd$ source bin/activate
+    (pd)~/pd$ 
+
+- Install Sphinx in the env::
+
+    (pd)~/pd$ easy_install sphinx
+    Searching for sphinx
+    Reading http://pypi.python.org/simple/sphinx/
+    Reading http://sphinx.pocoo.org/
+    Best match: Sphinx 0.6.4
+    ...
+    Finished processing dependencies for sphinx
+
+- Checkout the psycopg branch containing the documentation::
+
+    (pd)~/pd$ git clone git://github.com/dvarrazzo/psycopg2.git 
+    (pd)~/pd$ cd psycopg2/
+    (pd)~/pd/psycopg2$ git branch 
+    * docs
+
+- Build psycopg2 and ensure the package can be imported (it will be used for
+  reading the version number, autodocs etc.)::
+
+    (pd)~/pd/psycopg2$ python setup.py build
+    (pd)~/pd/psycopg2$ python setup.py install
+    running install
+    ...
+    creating ~/pd/lib/python2.6/site-packages/psycopg2
+    ...
+
+- Have the ``doc`` dir in the PYTHONPATH and run ``make`` from there::
+
+    (pd)~/pd/psycopg2$ cd doc/
+    (pd)~/pd/psycopg2/doc$ export PYTHONPATH=$(pwd):$PYTHONPATH
+    (pd)~/pd/psycopg2/doc$ make html
+    Running Sphinx v0.6.4
+    ...
+
+You should have the  in ``_build/html`` now.
+