Use extractbb instead of ebb

ebb was the old tool and looks like it is on its way out, a very least
from Debian and for pdfTeX.

From manpage:
-------------
 Here are more details about the bb and xbb formats:

 The original  ebb  (from dvipdfm) ignored density information in bitmap
 images, and generated bounding boxes with 100px = 72bp = 1in.  Unfortu‐
 nately, screenshots (especially) tend to look bad with this approach.

 So, extractbb (from dvipdfmx) uses density information if present.
 Otherwise, it generates bounding box with 100px = 100bp.  This is what
 pdfTeX does.

book/figures/fig-proofing-process.tex

@@ -11,7 +11,7 @@
   \path [line] (init) -- node{No} (retard_bake_decision);
   \path [line] (poke) -- (dent_visible_decision);
   \path [line] (dent_visible_decision) -- node{Yes} (bake);
-  \path [line] (dent_visible_decision.west) -- node{No} (dent_visible_decision.west -| wait_poke.south) -- node{} (wait_poke.south);
+  \path [line] (dent_visible_decision.west) -- node{No} ++(-1.4, 0) -- node{} (wait_poke.south);
   \path [line] (wait_poke) -- (poke);
   \path [line] (retard_bake_decision) -- node{Yes} (wait_retard);
   \path [line] (retard_bake_decision.east) -- node{No} ++(1, 0) |- node{} (retard.east);