Remove the 'Forms in WordPress' page

I've just been looking at the Forms in WordPress page to see if any of the URLs need to be updated (as per https://civicrm.org/blog/kcristiano/civicrm-526-and-wordpress-important-notice). But reading through it, I think all of this documentation is out of date and no longer required.

Instead of updating it, I suggest we just remove that page entirely.