made storage tanks' upper/lower fittings and intake grate fitting participate

in pipe autoplace algorithm

changelog.txt

@@ -3,7 +3,8 @@ Changelog
 
 2012-08-21: Made storage tank participate in autoplace algorithm.  Tuned API a 
 little to allow for more flexible placement.  Re-organized code a bit to allow 
-for some upcoming rules changes.
+for some upcoming rules changes.  Made storage tanks' upper/lower fittins and 
+intake grate participate in autoplace algorithm.
 
 2012-08-20: Added temporary nodes for storage tank and intake grating, but 
 without autoplace.