Permissions are incorrect

```
What steps will reproduce the problem?
1. prettytable is installed on Mac OS X Mavericks

What is the expected output? What do you see instead?
Whenever I try to run IPython notebook, I get a permissions error.

IOError: [Errno 13] Permission denied:
'/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/p
rettytable-0.7.2-py2.7.egg/EGG-INFO/top_level.txt'

I have to sudo IPython notebook in order to run it correctly, but this should
not happen.

What version of the product are you using? On what operating system?
prettytable0.7.2 on MacOS X Mavericks 10.9.4

Please provide any additional information below.
```

Original issue reported on code.google.com by `ericmaji...@gmail.com` on 8 Jul 2014 at 2:59

Start by reproducing the IPython notebook launch after installing prettytable 0.7.2 on Mac OS X Mavericks, then inspect the reported site-packages path and EGG-INFO/top_level.txt permissions. Done means IPython notebook runs without sudo and the package installation no longer causes a permission error.

Written by the indexing model from the issue text.