pgsql: In the recent changes to make the planner account better for

Log Message:
-----------
In the recent changes to make the planner account better for cache
effects in a nestloop inner indexscan, I had only dealt with plain index
scans and the index portion of bitmap scans. But there will be cache
benefits for the heap accesses of bitmap scans too, so fix
cost_bitmap_heap_scan() to account for that.

Modified Files:
--------------
pgsql/src/backend/optimizer/path:
costsize.c (r1.162 -> r1.163)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/path/costsize.c.diff?r1=1.162&r2=1.163)
indxpath.c (r1.210 -> r1.211)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/path/indxpath.c.diff?r1=1.210&r2=1.211)
pgsql/src/backend/optimizer/util:
pathnode.c (r1.130 -> r1.131)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/optimizer/util/pathnode.c.diff?r1=1.130&r2=1.131)
pgsql/src/include/optimizer:
cost.h (r1.76 -> r1.77)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/optimizer/cost.h.diff?r1=1.76&r2=1.77)
pathnode.h (r1.69 -> r1.70)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/optimizer/pathnode.h.diff?r1=1.69&r2=1.70)