Add depicts drop downs to the catalog page.

static/js/catalog.js

@@ -0,0 +1,38 @@
+var typingTimer;
+var doneTypingInterval = 500;
+
+var app = new Vue({
+    el: '#app',
+    delimiters: ['${', '}'],
+    data: {
+        prevTerms: {},
+        searchTerms: {},
+        hits: {},
+    },
+    methods: {
+        run_search(qid) {
+            var terms = this.searchTerms[qid];
+            if (terms == this.prevTerms[qid]) {
+                return;  // no change
+            }
+            this.prevTerms[qid] = terms;
+            if (terms.length < 3) {
+                this.hits[qid] = [];
+                return;
+            }
+
+            var vm = this;
+
+            fetch(lookup_url + '?terms=' + encodeURI(terms))
+                .then((res) => res.json())
+                .then((data) => {
+                    vm.hits[qid] = data.hits;
+                })
+        },
+        search(event) {
+            var qid = event.target.dataset.qid
+            clearTimeout(typingTimer);
+            typingTimer = setTimeout(this.run_search, doneTypingInterval, qid);
+        }
+    }
+});