Accept Answer URL should be idempotent and accept PUT or POST requests only

panel:bgColor=e7f4fa NOTE: This bug report is for Confluence Cloud. Using Confluence Server? See the corresponding bug report|http://jira.atlassian.com/browse/CONFSERVER-46610. panel Answers currently users a single URL to both accept and un-accept answers: noformat $baseurl/acceptanswer/$answeri...