Migration to typescript: first step

Add vue cli typescript support
Rename .js to .ts
Use class and annotations in App and NavBar
Add tslint

js/src/graphql/search.ts

@@ -0,0 +1,19 @@
+import gql from 'graphql-tag';
+
+export const SEARCH = gql`
+query SearchEvents($searchText: String!) {
+  search(search: $searchText) {
+    ...on Event {
+      title,
+      uuid,
+      __typename
+    },
+    ...on Actor {
+      avatarUrl,
+      domain,
+      preferredUsername,
+      __typename
+    }
+  }
+}
+`;