Add WinCE support.

* Added two new files: errno.hpp and errno.cpp. They are required to use errno functionality on WM.
* zmq.cpp, msg.h: removed inclusion of errno.h because it is included in zmq.h that is also included by .cpp.
* windows.hpp: process.h is included only for desktop builds.
* thread.cpp: on CE CreateThread is used instead of __beginthreadex
* socket_base.cpp, clock.cpp: on CE include cmnintrin.h instead on intrin.h
* signaler.cpp: on Windows should use special macro around event name (for unicode builds)
* err.hpp: make it include errno.hpp (my file) instead on errno.h when building for CE
* err.cpp: use FormatMessage when building for CE (because CE does not have ANSI API functions)
* zmq.h: do not include errno.h whe building for CE
* libzmq.vcproj: add tro new files

src/socket_base.cpp

@@ -29,8 +29,12 @@
 #if defined ZMQ_HAVE_WINDOWS
 #include "windows.hpp"
 #if defined _MSC_VER
+#if defined WINCE
+#include <cmnintrin.h>
+#else
 #include <intrin.h>
 #endif
+#endif
 #else
 #include <unistd.h>
 #endif