(svn r22405) -Document: some more "random-ish" tidbits

src/subsidy_type.h

@@ -14,8 +14,9 @@
 
 #include "core/enum_type.hpp"
 
+/** What part of a subsidy is something? */
 enum PartOfSubsidy {
-	POS_NONE =     0,
+	POS_NONE =     0, ///< nothing
 	POS_SRC = 1 << 0, ///< bit 0 set -> town/industry is source of subsidised path
 	POS_DST = 1 << 1, ///< bit 1 set -> town/industry is destination of subsidised path
 };