avoid using constant Int.neg

reactivated Find_Unused_Assms_Examples to avoid untested / dead stuff in the repository; moved the whole HOL-Quickcheck_Examples target from "all" to "full" for now -- it does not terminate in certain situations (to be investigated further);

merged

added lemma

converting "set [...]" to "{...}" in evaluation results

removing Find_Unused_Assms_Examples from session as it requires much time

restored accidental omission

dropped dead code

tuned structure

retain syntax here

tuned structure; dropped already existing syntax declarations

tuned syntax declarations; tuned structure

merged

marked candidates for rule declarations

include warning messages in node status;

tuned signature (in accordance with ML);

more PIDE modules;

tuned proofs;

more abstract class Document.State;

more abstract class Document.State.Assignment;

tuned signature;

more abstract class Document.Version; tuned (NB: Version.nodes is total);

more abstract class Document.Node;

more abstract class Document.History;

more abstract class Document.Change;

tuned;

tuned signature; clarified check;

merged

slightly changing the enumeration scheme

adding some more test invocations of find_unused_assms