Fix README typo
Fix typos and add missing ConfigurationError class.
Support App Engine along with regular Django applications.

* Add python 2.5 compatibility.
* Update the README.md file to include instructions for deploying on
  Google App Engine.
Make the README easier to follow.

* The example isn't suitable for private applications
* Added database creation step to regular django app
* Re-ordered App Engine instructions so that editing app.yaml
  it mentioned after downloading the source code containing it.
Remove dependancies of ShopifyAPI in README's easy_install command.

The dependancies are downloaded automatically now with easy_install,
with ShopifyAPI v0.1.3 released and uploaded.
Use code block markdown style in README.
Replaced the Shopify logo with a generic 'your logo here' image.

Simply to avoid copyright issues.
Update README with new links and pip installation instructions.
Modify to use OAuth2 authentication.
README: Stop linking to the outdated pre-configured zip file
Fix broken app link from admin.
README: OAuth2 is the only option for new apps.

No need to select it explicitly anymore.
Updated project structure for django version >= 1.4, changed to class based views
Removed print statment and sqlite file
Removed api keys from history
Removed google app engine from readme