Updated README
Updated README

We were still pointing to a previous release as the stable one.

Signed-off-by: Miquel Sabaté Solà <b4d70704b9e7df580cab34510621dbd0aacb2dfd@suse.com>

mssola/Portus,SUSE/Portus,SUSE/Portus,mssola/Portus,SUSE/Portus,SUSE/Portus,mssola/Portus,mssola/Portus