[Jenkins release job] README.md updated by release build 5.1.0.Beta2
[Jenkins release job] README.md updated by release build 5.1.0.Beta2

hibernate/hibernate-ogm,DavideD/hibernate-ogm-contrib,hibernate/hibernate-ogm,schernolyas/hibernate-ogm,DavideD/hibernate-ogm-cassandra,DavideD/hibernate-ogm,hibernate/hibernate-ogm,DavideD/hibernate-ogm,DavideD/hibernate-ogm-cassandra,hibernate/hibernate-ogm,schernolyas/hibernate-ogm,DavideD/hibernate-ogm-contrib,schernolyas/hibernate-ogm,Sanne/hibernate-ogm,Sanne/hibernate-ogm,DavideD/hibernate-ogm,DavideD/hibernate-ogm-contrib,Sanne/hibernate-ogm,Sanne/hibernate-ogm,DavideD/hibernate-ogm,DavideD/hibernate-ogm-cassandra