Since saas-3, website controllers use `request.website.render`
to render the template of a web page. This was kept for retro
compatibility. It's time to stop using deprecated stuff.
Same for `_render` method on website.
'json' route don't use `request.render` since
`JsonRequest` has no `render` method.
When submitting a track, you would expect to be follower of the track.
If you are logged in, you are automatically follower, if not and if a
partner with the e-mail given in the form exists, it will be added as
a follower.
Christophe Simonis