Merge pull request #1 from stelzzz/patch-1

Update currencies/management/commands/initcurrencies.py
Update INSTALL.txt

how to install latest version from Git
Add convert multicurrency function

Example of use:
price=convert(100, "RUB", "UAH")
Convert 100 Russian Rubles to Ukrainian Hryvnia (via base USD currency)
Update README.md
Update currencies/utils.py
Update currencies/templatetags/currency.py

add "currencuy_convert" template tag
Replace django.conf.urls.defaults with django.conf.urls for Django 1.6 compatibility.

Note, this breaks compatibility with Django <= 1.4
Serialize the currency_id rather than the currency, to work with Django 1.6 JSON serialization
Merge branch 'master' of https://github.com/stelzzz/django-currencies
Remove git install instructions as they don't point to the right repo
Name the template tag for conversion correctly, and some PEP8 tidy ups
Make the updatecurrencies command Python 2.6 compatible by converting floats to strings before turning them into Decimals
More Django 1.6 compatibility fixes - set the currency_id in the session, not the whole currency object
Merged with https://github.com/mysociety/django-currencies/commit/2dfb231dbaf3944f16e9838f7e9177da2eacf330