2010-02-13 wenzelm 2010-02-13 modernized structures;
2010-02-11 wenzelm 2010-02-11 numeral syntax: clarify parse trees vs. actual terms; modernized translations; formal markup of @{syntax_const} and @{const_syntax};
2009-10-17 wenzelm 2009-10-17 eliminated hard tabulators, guessing at each author's individual tab-width; tuned headers;
2008-03-01 wenzelm 2008-03-01 tuned ML code, more antiquotations;
2008-02-11 krauss 2008-02-11 Made theory names in ZF disjoint from HOL theory names to allow loading both developments in a single session (but not merge them).
2007-10-07 wenzelm 2007-10-07 modernized specifications; removed legacy ML bindings;
2007-05-31 wenzelm 2007-05-31 moved Integ files to canonical place;