possible fix for gmodule link error on some environments (#74). Updated copyright year.
differentiate DNS lookup error from connection errors.
imap.c: connect in another thread.
fixed the handling of GDK thread lock.
added SYL_ prefix to SockFlags enum to avoid confliction with recent glibc header file.
fixes stall of SMTP when sending via dialup connection.
prevented WSAEWOULDBLOCK on sending/receiving in Win32.
merged from LibSylph branch.
win32: implemented sock_set_nonblocking_mode().
win32: avoid blocking when reading from socket.
code cleanup of socket.c.
win32: implemented remote command using TCP socket.
changed the license of LibSylph from GPL to LGPL.
made some core modules library (libsylph).