Feature: Contact Panel with conversation details (#397)

* Add Contact panel changes

* Fix parent iframe blocked

* Add Conversation Panel, Contact messages

* Update contact panel with conversation details

* Update designs in sidebar

* Fix specs

* Specs: Add specs for conversationMetadata and contact modules

* Fix currentUrl issues

* Fix spelling

* Set default to empty string

app/javascript/widget/api/endPoints.js

@@ -3,6 +3,8 @@ const sendMessage = content => ({
   params: {
     message: {
       content,
+      timestamp: new Date().toString(),
+      referer_url: window.refererURL || '',
     },
   },
 });