Add stop-words, currencies, django-markwha, short_url, sanitize

Add following awesome python packages:

* python-stop-words: Get list of common stop words in various languages in Python.
* python-currencies: Display money format and its filthy currencies, for all money lovers out there.
* django-markwhat: A collection of template filters that implement common markup languages.
* short_url: Python implementation for generating Tiny URL- and bit.ly-like URLs.
* sanitize: Bringing sanity to world of messed-up data.