Upgrade to the latest Cataas API

They made a backwards-incompatible change when I wasn't looking :(

assets/js/bookmarks.js

@@ -80,7 +80,7 @@ const Bookmarks = (props) => {
             headers: {...headers,
                 "Content-Type": "application/json"
             },
-            body: JSON.stringify({ ...formState, remote_id: randomCat.id })
+            body: JSON.stringify({ ...formState, remote_id: randomCat._id })
         });
 
         // Update the category list in case a new one was added
@@ -112,7 +112,7 @@ const Bookmarks = (props) => {
             <div>
                 <img className = "random-image center-box-inner"
                     src = { randomCat != null
-                        ? cataas(randomCat.url)
+                        ? cataas("/cat/" + randomCat._id)
                         : null
                     }
                     alt = { randomCat != null