Merge pull request 'Detect language based on URL' (#4) from feature/automatic-language-switch into master

Reviewed-on: #4

da/index.html

@@ -31,7 +31,7 @@ vil være mistænkte for børnemisbrug.
 
 
 <div id="app-area">
-<object id="movie" data="../img/chatapp.svg" type="image/svg+xml"></object>
+<object id="movie" data="../img/chatapp.svg?lang=da" type="image/svg+xml"></object>
 <p id="movie-sidetext">
 Lær mere om ChatControllen og hvorfor det er en dårlig idé, i vores interaktive ChatControl film ude til venstre.
 </p>

en/index.html

@@ -32,7 +32,7 @@ will be treated as suspects for child abuse.
 </p>
 
 <div id="app-area">
-<object id="movie" data="../img/chatapp.svg" type="image/svg+xml"></object>
+<object id="movie" data="../img/chatapp.svg?lang=en" type="image/svg+xml"></object>
 <p id="movie-sidetext">
 Learn more about Chat Control and why it is a bad idea by watching our
 interactive film on the left.

img/chatapp.svg

@@ -68,7 +68,9 @@ const typing_speed = 50;
 
 var conversation_count = 0;
 var current_dialog = null;
-var current_language = "da";
+
+var current_language = new URLSearchParams(location.search).get('lang') ?? 'da';
+
 var current_dialog_fn = null;
 
 /// SVG 1.1 doesn't do proper text splitting into several lines.