source and target versions changed to support java7/8
source and target versions changed to support java7/8

bsenduran/wso2-commons-vfs,bsenduran/wso2-commons-vfs,sandamal/wso2-commons-vfs,raviu/wso2-commons-vfs,bsenduran/wso2-commons-vfs,raviu/wso2-commons-vfs,raviu/wso2-commons-vfs,virajsenevirathne/wso2-commons-vfs,virajsenevirathne/wso2-commons-vfs,sandamal/wso2-commons-vfs,virajsenevirathne/wso2-commons-vfs,sandamal/wso2-commons-vfs