Added translation keyz

ref #48

src/components/groups/Groups.svelte

@@ -9,7 +9,7 @@
 
 <section class="container p-5">
   <span class="mb-1 text-3xl font-extrabold leading-tight">
-    User Groups
+    {$_('user-groups')}
     {#if store.state.jwtinfo.userdetails.permissions.includes('USERGROUP:CREATE')}
       <button
         on:click={() => {
@@ -17,7 +17,7 @@
         }}
         type="button"
         class="w-full inline-flex justify-center rounded-md border border-transparent shadow-sm px-4 py-2 bg-blue-600 text-base font-medium text-white hover:bg-blue-700 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-blue-500 sm:ml-3 sm:w-auto sm:text-sm">
-        Add User Group
+        {$_('add-user-group')}
       </button>
     {/if}
   </span>