Loads up all posts made by a user for the "Show Posts" section of their profile.

• Called from ModifyProfile
• Accessed at ?action=profile;sa=showPosts or ?action=profile;u={user_id};sa=showPosts
• Determines how many posts to show based on $_REQUEST['viewcount'] (will show 10 if this isn't set or isn't numeric)
• Allows the person viewing the posts to delete or reply to the posts if they have permission to do so
• Allows other users to request notifications for these posts if they have permission to do so
• Post information is loaded into $context['posts'] array