Split the generation of images up to use a larger font on 1-9, and
smaller on 10-30 to further improve the appearance.
s/seq/jot/ so users on < 9.x can run this script
Submitted by: gjb [1]
callouts with consistent number icons. Callouts above number 15 would
still be displayed in bracketed text.
Obtained from: docbook-xsl distribution
Created by: Dave Pawson
