libssh2 1.2.1

This release includes the following changes:

 o generate and install libssh2.pc

This release includes the following bugfixes:

 o proper return codes returned from several functions
 o return EAGAIN internal cleanup
 o added knownhost.c to windows makefiles
 o pass private-key to OpenSSL as a filename with BIO_new_file().
 o make libssh2_scp_send/recv do blocking mode correctly
 o libssh2_channel_wait_closed() could hang
 o libssh2_channel_read_ex() must return 0 when closed
 o added gettimeofday() function for win32 for the debug trace outputs
 o transport layer bug causing invalid -39 (LIBSSH2_ERROR_BAD_USE) errors
 o scp examples now loop correctly over libssh2_channel_write()

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

 Peter Stuge, Neil Gierman, Steven Van Ingelgem, Alexander Lamaison,
 Guenter Knauf, Simon Josefsson
 

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