Support 'alias' calls in e2e tests

bin/analytics

@@ -39,6 +39,7 @@ command :send do |c|
   c.option '--traits=<traits>', 'the identify/group traits to send (JSON-encoded)'
 
   c.option '--groupId=<groupId>', String, 'the group id'
+  c.option '--previousId=<previousId>', String, 'the previous id'
 
   c.action do |args, options|
     Analytics = Segment::Analytics.new({
@@ -91,6 +92,14 @@ command :send do |c|
         context: json_hash(options.context),
         integrations: json_hash(options.integrations)
       })
+    when "alias"
+      Analytics.alias({
+        previous_id: options.previousId,
+        user_id: options.userId,
+        anonymous_id: options.anonymousId,
+        context: json_hash(options.context),
+        integrations: json_hash(options.integrations)
+      })
     else
       raise "Invalid Message Type #{options.type}"
     end