More localization (#358)

* Translate missing items on About page

* Localize import summary dialog

* Make site menu translation reactive

* Localize import options

* Include semi colon in string

* Move API texts to frontend + better status codes

* Provide feedback to user when no meal is planned

* Fix API tests after latest rework

* Add warning for API changes in changelog

* Refactor API texts handling

* Refactor API texts handling #2

* Better API feedback

* Rearrange strings hierarchy

* Add messages upon recipe updated

* Fix 'recipe effected' typo

* Remove snackbar usage in backend

* Translate toolbox

* Provide feedback for tags CRUD

* Fix messed up merge

* Translate sign-up form

* Better feedback for sign-up CRUD

* Refactor log-in API texts handling

* No error message when user is not authenticated

* Remove unimportant console log

frontend/src/pages/SearchPage/index.vue

@@ -26,7 +26,7 @@
       <v-row dense class="mt-0 flex-row align-center justify-space-around">
         <v-col>
           <h3 class="pl-2 text-center headline">
-            {{ $t("search.category-filter") }}
+            {{ $t("category.category-filter") }}
           </h3>
           <FilterSelector class="mb-1" @update="updateCatParams" />
           <CategoryTagSelector