Add tracking of signups on the WordPress plugin

Add tracking of signups on the WordPress plugin by passing GET param
p=integration, this commit is related to RedMine issue #1270
Version of the plugin must be 3.0.3 (same as the changelog).

Version of the plugin must be 3.0.3 (same as the changelog)
Add tracking of signups on the WordPress plugin

Add tracking of signups on the WordPress plugin
Change the comment from the Changelog

Change the comment from the Changelog
Change the p parameter from integration to wordpress-3.0

Change the p parameter from integration to wordpress-3.0