Set al_user_language & session_local.al_user_language always

[plocket]

I'm unsure how to test this change and I'm hunting that down now. It's a suggestion to handle a user report:

When I change the language at the beginning of the interview using:

${ get_language_list(lang_codes=al_interview_languages, current=al_user_language) }

the interview screens translate, but the program assembles English forms. Usually when I get to the code block that determines which ALDocuments are enabled, this check will work:

if session_local.attr("al_user_language") == "es"

For some reason it isn't when I use the get_language_list() function to change the language. If I use the language picker in the menu bar, and cycle es > en > es, then the correct Spanish documents assemble.