make dht test program able to get and put mutable items. fixed some DHT bugs along the mutable put/get path

git-svn-id: http://libtorrent.googlecode.com/svn/trunk@9750 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
update dht unit test

git-svn-id: http://libtorrent.googlecode.com/svn/trunk@9751 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
merged http_connection tweak from RC_0_16

git-svn-id: http://libtorrent.googlecode.com/svn/trunk@9754 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
reorder the node-list in the DHT traversal algorithm if a node updates its ID

git-svn-id: http://libtorrent.googlecode.com/svn/trunk@9755 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
fix ip_voter to detect changing IPs

git-svn-id: http://libtorrent.googlecode.com/svn/trunk@9758 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda