Update plugin 'http_accept_language' to version that supports Rails 3.1.
Install 'rails_legacy_mapper' so we don't have to update all routes.
This should be temporary.
Update Session configuration.
Update path configuration.
Load the correct sass file.
debug_rjs was removed.
ActiveRecord::Associations::AssociationProxy was split into multiple classes.
Use ActiveRecord::Associations::CollectionProxy.
RAILS_DEFAULT_LOGGER is not defined anymore.