update Prerequisites

To build without error, you must install pyqt4-dev-tools, after install pyqt4-dev-tools, you don't have to install python-qt4, it's already included in pyqt4-dev-tools.

Author: qu4n

README.md

@@ -15,9 +15,9 @@ This software is free and open source software licensed under the terms of GPLv3
 
 * Python 2.7 or 2.6 (or 3.x)
 
-* PyQt
+* Development tools for PyQt4
 
-    - `python-qt4` (Ubuntu/Mint/Debian), `python-pyqt4` (Arch Linux)
+    - `pyqt4-dev-tools` (Ubuntu/Mint/Debian), `pyqt4-dev-tools` (Arch Linux)
 
 * lxml