improve README

README.rst

@@ -23,12 +23,12 @@ Getting started
 Electrum is a pure python application. However, if you want to use the
 Qt interface, then you need to install the Qt dependencies::
 
-    sudo apt-get install python-pip python-qt4
-
+    sudo apt-get install python-qt4
 
 If you downloaded the official package (tar.gz), then you can run
 Electrum from its root directory, without installing it on your
-system. To run Electrum from this directory, just do::
+system; all the python dependencies are included in the 'packages'
+directory. To run Electrum from its root directory, just do::
 
     ./electrum
 
@@ -94,6 +94,7 @@ In oder to creating binaries, you must create the 'packages' directory::
 
     ./contrib/make_packages
 
+This directory contains the python dependencies used by Electrum.
 
 Mac OS X
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