(libT) add '#include errno.h' to announcer-udp.c to ensure errno is declared

git-svn-id: svn://svn.transmissionbt.com/Transmission/trunk@13965 f4695dd4-2c0a-0410-b89c-da849a56a58e
(libT) when logging on win32, use OutputDebugStringA instead of OutputDebugString

git-svn-id: svn://svn.transmissionbt.com/Transmission/trunk@13966 f4695dd4-2c0a-0410-b89c-da849a56a58e
(libT) add rb07's win32 implementation of tr_is_same_file().

git-svn-id: svn://svn.transmissionbt.com/Transmission/trunk@13967 f4695dd4-2c0a-0410-b89c-da849a56a58e