(svn r14104) -Feature: Add a window for waypoints, allowing to view all the trains having the selected waypoint in their orders.

Changing its name is also supported from the same new window.
Gui based on work done by Satyap, on FS#2025.

src/window_type.h

@@ -94,6 +94,7 @@ enum WindowClass {
 	WC_BUILD_SIGNAL,
 	WC_COMPANY_PASSWORD_WINDOW,
 	WC_OSK,
+	WC_WAYPOINT_VIEW,
 
 	WC_INVALID = 0xFFFF
 };