merge remap_files unit test from RC_0_16

git-svn-id: http://libtorrent.googlecode.com/svn/trunk@9763 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
fix windows build

git-svn-id: http://libtorrent.googlecode.com/svn/trunk@9764 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
export ed25519 functions from libtorrent. fix tools/dht_put build when dht is disabled. fix shared linking in tools Jamfile

git-svn-id: http://libtorrent.googlecode.com/svn/trunk@9765 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda
merged fixes from RC_0_16

git-svn-id: http://libtorrent.googlecode.com/svn/trunk@9768 f43f7eb3-cfe1-5f9d-1b5f-e45aa6702bda