Merge branch 'master' into jgrpp

# Conflicts:
#	cmake/scripts/FindVersion.cmake
#	src/airport_gui.cpp
#	src/industry_gui.cpp
#	src/newgrf.cpp
#	src/newgrf_class_func.h
#	src/newgrf_object.h
#	src/newgrf_roadstop.cpp
#	src/newgrf_roadstop.h
#	src/object_gui.cpp
#	src/rail_gui.cpp
#	src/road_cmd.h
#	src/road_gui.cpp
#	src/station_cmd.h
#	src/strings.cpp
#	src/waypoint_cmd.h

src/newgrf_object.h

@@ -64,9 +64,9 @@ void ResetObjects();
 
 /** Class IDs for objects. */
 enum ObjectClassID : uint16_t {
-	OBJECT_CLASS_BEGIN   =      0, ///< The lowest valid value
-	OBJECT_CLASS_MAX     = 0xFFFF, ///< Maximum number of classes.
-	INVALID_OBJECT_CLASS = 0xFFFF, ///< Class for the less fortunate.
+	OBJECT_CLASS_BEGIN   = 0,          ///< The lowest valid value
+	OBJECT_CLASS_MAX     = UINT16_MAX, ///< Maximum number of classes.
+	INVALID_OBJECT_CLASS = UINT16_MAX, ///< Class for the less fortunate.
 };
 /** Allow incrementing of ObjectClassID variables */
 DECLARE_POSTFIX_INCREMENT(ObjectClassID)