Updated JS translations to be inserted from back-end

Removes old awkward JS translations endpoint.
New system still a little akward in code but not now in process.

Also extracted out page editors into their own files.

Closes #1258

app/Providers/AppServiceProvider.php

@@ -39,6 +39,14 @@ class AppServiceProvider extends ServiceProvider
             return "<?php echo icon($expression); ?>";
         });
 
+        Blade::directive('exposeTranslations', function($expression) {
+            return "<?php \$__env->startPush('translations'); ?>" .
+                "<?php foreach({$expression} as \$key): ?>" .
+                '<meta name="translation" key="<?php echo e($key); ?>" value="<?php echo e(trans($key)); ?>">' . "\n" .
+                "<?php endforeach; ?>" .
+                '<?php $__env->stopPush(); ?>';
+        });
+
         // Allow longer string lengths after upgrade to utf8mb4
         Schema::defaultStringLength(191);