libtorrent-1.2.9

1.2.9 released

• add macro TORRENT_CXX11_ABI for clients building with C++14 against
  libtorrent build with C++11
• refreshed m4 scripts for autotools
• removed deprecated wstring overloads on non-windows systems
• drop dependency on Unicode's ConvertUTF code (which had a license
  incompatible with Debian)
• fix bugs exposed on big-endian systems
• fix detection of hard-links not being supported by filesystem
• fixed resume data regression for seeds with prio 0 files