improve connection tester to support non-fast-extension clients and to be multi-threaded
improve connection tester to support non-fast-extension clients and to be multi-threaded

git-svn-id: 6ed3528c1be4534134272ad6dd050eeaa1f628d3@5808 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda

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