fix the created at bug

packages/rocketchat-statistics/server/functions/get.coffee

@@ -3,7 +3,7 @@ RocketChat.statistics.get = ->
 
 	# Version
 	statistics.uniqueId = RocketChat.settings.get("uniqueID")
-	statistics.createdAt = RocketChat.models.Settings.findOne("uniqueID")?._createdAt
+	statistics.installedAt = RocketChat.models.Settings.findOne("uniqueID")?.createdAt
 	statistics.version = RocketChat.Info?.version
 	statistics.tag = RocketChat.Info?.tag
 	statistics.branch = RocketChat.Info?.branch

packages/rocketchat-ui-admin/admin/adminInfo.html

@@ -24,7 +24,7 @@
 					</tr>
 					<tr>
 						<th>{{_ "Installed_at"}}</th>
-						<td>{{statistics.createdAt}}</td>
+						<td>{{statistics.installedAt}}</td>
 					</tr>
 					<tr>
 						<th>{{_ "Uptime"}}</th>