added some virtual relationships; use add_memberships instead of calling 'new' on the membership object class
added some virtual relationships; use add_memberships instead of calling 'new' on the membership object class

muffato/public-plugins,andrewyatz/public-plugins,muffato/public-plugins,andrewyatz/public-plugins,andrewyatz/public-plugins,muffato/public-plugins,Ensembl/public-plugins,Ensembl/public-plugins,muffato/public-plugins,Ensembl/public-plugins,andrewyatz/public-plugins,andrewyatz/public-plugins