(svn r2906) Fix some threaded saving problems. Now the thread only interfaces with the main program through a sort of mutex. Communication uses the function OTTD_SendThreadMessage() with the approiate message which is handled in ProcessSentMessage() during the main loop.

functions.h

@@ -276,4 +276,5 @@ int ttd_main(int argc, char* argv[]);
 void DeterminePaths(void);
 
 void bubblesort(void *base, size_t nmemb, size_t size, int(*compar)(const void *, const void *));
+void CSleep(int milliseconds);
 #endif /* FUNCTIONS_H */