i18n Improvements

I'm not sure if these are beyond the scope, but there's one bugfix and a few small additions to help improve translating plugins. Here a couple links with more details:

* http://geertdedeckere.be/article/loading-wordpress-language-files-the-right-way
* http://www.cssigniter.com/ignite/wordpress-poedit-translation-secrets/

And thanks for putting this together. It's a pretty awesome resource!