Add some notes about releasing plugin
Add some notes about releasing plugin

remusb/saml-plugin,remusb/saml-plugin,Sauraus/saml-plugin,jenkinsci/saml-plugin,jenkinsci/saml-plugin,jenkinsci/saml-plugin,robingarner/saml-plugin,Brantone/saml-plugin,Sauraus/saml-plugin,Brantone/saml-plugin,robingarner/saml-plugin