docs: remove CentOS 5 build instructions

It's EOL in a few days and the instructions only add confusion.
Anyone still using CentOS 5 has bigger issues than not having
documentation on how to build Minecraft-Overviewer.

docs/building.rst

@@ -182,42 +182,3 @@ You may need or want to add the line::
     PYTHON_VERSION=2.7
 
 to the file /etc/make.conf, but read the ports documentation to be sure of what this might do to other Python applications on your system.
-
-.. _centos:
-
-CentOS 5
---------
-
-.. note::
-
-    If you are using CentOS 6, you do not need to install the epel repo.
-    CentOS 6 should come with the right python version, you can check
-    your version running *python --version*.
-
-Since CentOS has an older version of Python (2.4), there are some difficulties
-in getting the Overviewer to work. Follow these steps which have been reported
-to work.
-
-Note: commands prefixed with a "#" mean to run as root, and "$" mean to run as a
-regular user.
-
-1. Install the `EPEL repo <http://fedoraproject.org/wiki/EPEL>`_. Go to step #2 if you already have the EPEL repo installed.
-
-  1. ``$ wget http://download.fedoraproject.org/pub/epel/5/i386/epel-release-5-4.noarch.rpm``
-  2. ``# rpm -Uhv epel-release-5-4.noarch.rpm``
-
-2. Install the python26 packages and build dependancies
-
-  1. ``# yum install -y python26{,-imaging,-numpy}{,-devel} gcc``
-
-3. Install and setup Overviewer
-
-  1. ``$ git clone git://github.com/overviewer/Minecraft-Overviewer.git``
-  2. ``$ cd Minecraft-Overviewer``
-  3. ``$ python26 setup.py build``
-  4. Change the first line of overviewer.py from ``#!/usr/bin/env python`` to ``#!/usr/bin/env python26`` so that the Python 2.6 interpreter is used instead of the default 2.4
-
-4. Run Overviewer as usual
-
-  1. ``$ ./overviewer.py path/to/world/ path/to/output/`` or ``$ python26 path/to/overviewer.py path/to/world/ path/to/output/``
-  2. Proceed to the :doc:`Running <running>` instructions for more info.