ANSI C fixes.
Removed warnings.
Made the include files self-sufficient.
Some Solaris fixes.

diff --git a/windows/multimon.c b/windows/multimon.c
index 5dc3987..e8b407a 100644
--- a/windows/multimon.c
+++ b/windows/multimon.c
@@ -21,7 +21,7 @@
 /***********************************************************************
  *              MONITOR_GetMonitor
  */
-MONITOR *MONITOR_GetMonitor(HMONITOR hMonitor)
+static MONITOR *MONITOR_GetMonitor(HMONITOR hMonitor)
 {
   if(hMonitor == xPRIMARY_MONITOR)
     {