add thumbnail URL to KaleidoscopeEvent model

app/models/kaleidoscope-event.js

@@ -15,6 +15,7 @@ const KaleidoscopeEventSchema = new Schema({
   label: { type: String },
   content: { type: String },
   href: { type: String },
+  thumbnail: { type: String },
   source: {
     pkg: {
       name: { type: String, required: true },

app/services/hive.js

@@ -195,6 +195,10 @@ class HiveService extends SiteService {
     event.content = striptags(eventDefinition.content.trim());
     event.href = striptags(eventDefinition.href.trim());
 
+    if (eventDefinition.thumbnail) {
+      event.thumbnail = striptags(eventDefinition.thumbnail);
+    }
+
     event.source = {
       pkg: {
         name: striptags(eventDefinition.source.pkg.name.trim().toLowerCase()),