libssh2 1.2.3

This release includes the following changes:

 o ssh-agent support with the new libssh2_agent_* functions
 o Added libssh2_trace_sethandler()
 o Added the direct_tcpip.c and ssh2_agent.c examples

This release includes the following bugfixes:

 o Fixed memory leak in userauth_publickey
 o Fixed publickey authentication regression
 o Silenced several compiler warnings
 o avoid returning data to memory already freed
 o transport layer fix for bogus -39 (LIBSSH2_ERROR_BAD_USE) errors
 o Fixed padding in ssh-dss signature blob encoding
 o Fixed direction blocking flag problems
 o Fixed memory leak in sftp_fstat()

This release would not have looked like this without help, code, reports and
advice from friends like these:

 Simon Josefsson, Peter Stuge, Daiki Ueno, Dave McCaldon,
 Alexander Lamaison
 

        Thanks! (and sorry if I forgot to mention someone)