Merge branch 'stable'

* stable:
  Update 2.1.2.3 release notes
  Fix enter causing miscompletion of new project watches
  Fix enter causing miscompletion of group names on access rights
  Advertise our relying party XRDS document
  Use OpenID PAPE extension to force reauthentication
  Allow gitweb assets to be cached by browser
  Serve gitweb.js when serving gitweb.cgi
  Correct gitweb servlet copyright notices
  create-project: Don't destroy description of repository