Add direction support

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@ulms/events",
-  "version": "0.1.1",
+  "version": "0.1.2",
   "description": "JavaScript API-client for uLMS Events service",
   "files": [
     "es",

src/events.js

@@ -24,13 +24,19 @@ export class HttpEventsResource {
     }
   }
   getState (audience, roomId, params = {}) {
-    const { offset } = params
-    let qs = ''
+    const { offset, direction } = params
+    const qsParts = []
 
     if (!isNaN(offset)) {
-      qs = `?offset=${offset}`
+      qsParts.push(`offset=${offset}`)
     }
 
+    if (~['forward', 'backward'].indexOf(direction)) {
+      qsParts.push(`direction=${direction}`)
+    }
+
+    const qs = qsParts.length ? `?${qsParts.join('&')}` : ''
+
     return this.tokenProvider.getToken()
       .then((token) =>
         this.httpClient.get(