On the fsfs-format7 branch: Teach the fsfs-access-map tool to
generate scaled / rectangular heatmaps as well.

* tools/dev/fsfs-access-map.c
  (color_t): declare a new data type
  (add_sample,
   scale_line): new scaling utility functions
  (write_bitmap): add scaling option
  (main): generate scaled and non-scaled heat maps


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/fsfs-format7@1491784 13f79535-47bb-0310-9956-ffa450edef68