Update IPython installation instructions

python-intro/README

@@ -15,10 +15,7 @@ virtual environment like this (on Debian Wheezy):
 
 We need IPython 1.0 which is not yet released, so we get it from GitHub:
 
-    git clone https://github.com/ipython/ipython.git /tmp/ipython
-    pushd /tmp/ipython
-    python setup.py install
-    popd
+    pip install -e git+https://github.com/ipython/ipython#egg=ipython
 
 If IPython 1.0 is released, you can just do this:
 
@@ -42,6 +39,13 @@ For matplotlib, we need some development and system packages:
     pip install matplotlib
     echo "backend : GTKCairo" >> ~/.matplotlib/matplotlibrc
 
+If you want the IPython qtconsole to work, I found the following snippet to
+take PyQT from system packages:
+
+    https://gist.github.com/jlesquembre/2042882
+
+We might want to use the same approach for the PyGTK/PyCAIRO stuff above.
+
 
 Editing the slides
 ------------------