No need for <io.h> on Win32.

* libgimp/gimp.c: No need for <io.h> on Win32.

	* libgimp/{gimp,gimpui}.def: Add two entry points.

	* libgimp/gimp.h: Can't use __declspec(dllexport) for PLUG_IN_INFO
	when compiling with gcc on Win32. Also handle __argc, __argv and
	_stdcall differently with gcc on Win32

	* libgimp/gimpenv.c: Include <string.h>.

	* libgimp/gimpfeatures.h.in: Remove lots of extraneous trailing blanks.

	* libgimp/gimpfileselection.c: Include <glib.h> early, see above.

	* libgimp/{gimpwire,parasite}.c: Test for NATIVE_WIN32, not
	_MSC_VER.

	* libgimp/makefile.msc: Miscellaneous updates. The gimpi library
 	is now built as a static library.

libgimpwidgets/gimpfileentry.c

@@ -21,6 +21,9 @@
  */
 
 #include "config.h"
+
+#include <glib.h>		/* Needed here by Win32 gcc compilation */
+
 #include <sys/types.h>
 #include <sys/stat.h>
 #ifdef HAVE_UNISTD_H

libgimpwidgets/gimpfileselection.c

@@ -21,6 +21,9 @@
  */
 
 #include "config.h"
+
+#include <glib.h>		/* Needed here by Win32 gcc compilation */
+
 #include <sys/types.h>
 #include <sys/stat.h>
 #ifdef HAVE_UNISTD_H