Log Message:
libtorrent-rasterbar: updated to 2.0.6

libtorrent-2.0.6

fix issue creating a v2 torrent from torrent_info containing an empty file
make recheck files also update which files use partfile
add write_through disk_io_write_mode, which flushes pieces to disk immediately
improve copy file function to preserve sparse regions (when supported)
add function to truncate over-sized files part of a torrent
fix directory creation on windows shared folders
add flag to make add_files() not record file attributes
deprecate (unused) allow_partial_disk_writes settings
fix disk-full error reporting in mmap_disk_io
fixed similar-torrents feature for v2 torrents
fix potential unbounded recursion in add_completed_job, in disk I/O
deprecated (unused) volatile_read_cache setting
fix part files being marked as hidden on windows