2012-07-26 wenzelm 2012-07-26 remove old output heaps, to ensure that result is valid wrt. check_stamps; tuned signature;
2012-07-23 wenzelm 2012-07-23 added system build mode: produce output in ISABELLE_HOME; determine output location more explicitly;
2012-07-21 wenzelm 2012-07-21 tuned -- no dependency on exit function;
2012-07-20 wenzelm 2012-07-20 further imitation of "usedir" shell script; Pure/build observes build_images option, unlike traditional version; tuned signature;
2012-07-20 wenzelm 2012-07-20 simplified script to build Isabelle/ML;