Add Django-localeurl to the translation/i18n documentation

[vizualbod]

​http://code.google.com/p/django-localeurl/ should really be included in the translation documentation. I was very fortunate to digg it with great help of folks on IRC:

Suppose you have a Django website in multiple languages. The localeurl application ​http://code.google.com/p/django-localeurl/ allow you to specify the language of a page in the URL, like so: ​http://www.example.com/nl/company/profile. Any URLs without language prefix will be redirected to add the prefix for the default language.

Some reasons for using localeurl:

• Search engines will index all languages.
• Every page should have a unique URL. If you feel that different languages means different pages, then each language should get its own unique URL.
• Setting the language for the website should be done using a POST request (because it influences subsequent page views, see Django ticket #3651). You might not want to use POST requests.

[Ramiro Morales]

So far adding a links to third party django-* projects that don't provide core functionality hasn't been done in the Django documentation. Maybe Creating an appropiate wiki page would be enough?

[Ramiro Morales]

Fortunately the ecosystem of third party applications is thriving. This is unfortunate for this ticket because IMHO it isn't a good idea to add pointers to such applications to the Django main documentation, third party apps come and go (unmaintained, etc.) and the burden of verifying the relevance of such projects and maintaining the links would be on Django developers. Also, such links could be interpreted as some sort of endorsement.

As suggested above, a solution adopted in the past has been that users (any user) create and, more importantly, maintain a page in the Django Wiki with this kind of content.

See #11585 for news in this front (including links to apps that solve this problem in different ways).