Enabled translation when not logged in

Reads from the Accept-Language HTTP header.
Also fixed some encoding for ES translations.

Fixes #375

@@ -46,7 +46,7 @@ class HomeController extends Controller
      * @return \Illuminate\Contracts\Routing\ResponseFactory|\Symfony\Component\HttpFoundation\Response
      */
     public function getTranslations() {
-        $locale = trans()->getLocale();
+        $locale = app()->getLocale();
         $cacheKey = 'GLOBAL_TRANSLATIONS_' . $locale;
         if (cache()->has($cacheKey) && config('app.env') !== 'development') {
             $resp = cache($cacheKey);

@@ -15,7 +15,17 @@ class Localization
     public function handle($request, Closure $next)
     {
         $defaultLang = config('app.locale');
+        if (user()->isDefault()) {
+            $locale = $defaultLang;
+            $availableLocales = config('app.locales');
+            foreach ($request->getLanguages() as $lang) {
+                if (!in_array($lang, $availableLocales)) continue;
+                $locale = $lang;
+                break;
+            }
+        } else {
             $locale = setting()->getUser(user(), 'language', $defaultLang);
+        }
         app()->setLocale($locale);
         Carbon::setLocale($locale);
         return $next($request);

@@ -58,6 +58,7 @@ return [
     */
 
     'locale' => env('APP_LANG', 'en'),
+    'locales' => ['en', 'de', 'es', 'fr', 'nl', 'pt_BR', 'sk'],
 
     /*
     |--------------------------------------------------------------------------

@@ -44,6 +44,8 @@ Once done you can run `phpunit` in the application root directory to run all tes
 
 As part of BookStack v0.14 support for translations has been built in. All text strings can be found in the `resources/lang` folder where each language option has its own folder. To add a new language you should copy the `en` folder to an new folder (eg. `fr` for french) then go through and translate all text strings in those files, leaving the keys and file-names intact. If a language string is missing then the `en` translation will be used. To show the language option in the user preferences language drop-down you will need to add your language to the options found at the bottom of the `resources/lang/en/settings.php` file. A system-wide language can also be set in the `.env` file like so: `APP_LANG=en`.
 
+You will also need to add the language to the `locales` array in the `config/app.php` file.
+ 
  Some strings have colon-prefixed variables in such as `:userName`. Leave these values as they are as they will be replaced at run-time.
  
 ## Contributing

@@ -166,7 +166,7 @@ return [
         'start_a' => ':count usuarios han comenzado a editar esta página',
         'start_b' => ':userName ha comenzado a editar esta página',
         'time_a' => 'desde que las página fue actualizada',
-        'time_b' => 'en los Ãltimos :minCount minutos',
+        'time_b' => 'en los últimos :minCount minutos',
         'message' => ':start :time. Ten cuidado de no sobreescribir los cambios del otro usuario',
     ],
     'pages_draft_discarded' => 'Borrador descartado, el editor ha sido actualizado con el contenido de la página actual',
@@ -189,7 +189,7 @@ return [
     'attachments_set_link' => 'Setear Link',
     'attachments_delete_confirm' => 'Haga click en borrar nuevamente para confirmar que quiere borrar este adjunto.',
     'attachments_dropzone' => 'Arrastre ficheros aquío haga click aquípara adjuntar un fichero',
-    'attachments_no_files' => 'NingÃn fichero ha sido adjuntado',
+    'attachments_no_files' => 'Ningún fichero ha sido adjuntado',
     'attachments_explain_link' => 'Ud. puede agregar un link o si lo prefiere puede agregar un fichero. Esto puede ser un link a otra página o un link a un fichero en la nube.',
     'attachments_link_name' => 'Nombre de Link',
     'attachment_link' => 'Link adjunto',

@@ -14,6 +14,23 @@ class LanguageTest extends TestCase
         $this->langs = array_diff(scandir(resource_path('lang')), ['..', '.']);
     }
 
+    public function test_locales_config_key_set_properly()
+    {
+        $configLocales = config('app.locales');
+        sort($configLocales);
+        sort($this->langs);
+        $this->assertTrue(implode(':', $this->langs) === implode(':', $configLocales), 'app.locales configuration variable matches found lang files');
+    }
+
+    public function test_correct_language_if_not_logged_in()
+    {
+        $loginReq = $this->get('/login');
+        $loginReq->assertSee('Log In');
+
+        $loginPageFrenchReq = $this->get('/login', ['Accept-Language' => 'fr']);
+        $loginPageFrenchReq->assertSee('Se Connecter');
+    }
+
     public function test_js_endpoint_for_each_language()
     {