added isSingleton()
added isSingleton()

pferraro/JGroups,dimbleby/JGroups,deepnarsay/JGroups,ibrahimshbat/JGroups,danberindei/JGroups,ibrahimshbat/JGroups,TarantulaTechnology/JGroups,dimbleby/JGroups,ibrahimshbat/JGroups,pruivo/JGroups,kedzie/JGroups,rhusar/JGroups,dimbleby/JGroups,pruivo/JGroups,danberindei/JGroups,ligzy/JGroups,pruivo/JGroups,vjuranek/JGroups,ibrahimshbat/JGroups,tristantarrant/JGroups,deepnarsay/JGroups,rvansa/JGroups,rvansa/JGroups,Sanne/JGroups,rpelisse/JGroups,kedzie/JGroups,slaskawi/JGroups,TarantulaTechnology/JGroups,kedzie/JGroups,belaban/JGroups,slaskawi/JGroups,danberindei/JGroups,Sanne/JGroups,Sanne/JGroups,ligzy/JGroups,rhusar/JGroups,belaban/JGroups,slaskawi/JGroups,vjuranek/JGroups,ligzy/JGroups,rpelisse/JGroups,tristantarrant/JGroups,TarantulaTechnology/JGroups,deepnarsay/JGroups,pferraro/JGroups,pferraro/JGroups,rpelisse/JGroups,vjuranek/JGroups,belaban/JGroups,rhusar/JGroups