The initial captcha plugin was superseeded by an improved captcha module in
XWIKI-4779. However, the transition left out some:
- mentions in XWiki.RegistrationHelp about needing to enable the old captcha plugin first (
- an ancient API method that basically is now always returning false in c.x.x.XWiki.hasCaptcha(XWikiContext context)
These need to be removed as well.