fixed potential problem if there are not enough references to a peer_connection when its disconnected
fixed potential problem if there are not enough references to a peer_connection when its disconnected

git-svn-id: 6ed3528c1be4534134272ad6dd050eeaa1f628d3@3211 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda

steeve/libtorrent,steeve/libtorrent,steeve/libtorrent,steeve/libtorrent,steeve/libtorrent,steeve/libtorrent