updated readme
updated readme

bethadele/open-badges-issuer-addon,ubc/open-badges-issuer-addon,mhawksey/open-badges-issuer-addon,bethadele/open-badges-issuer-addon,credil/open-badges-issuer-addon,mhawksey/open-badges-issuer-addon,ubc/open-badges-issuer-addon,credil/open-badges-issuer-addon