more explicit error messages; clarified signature;

more explicit errors; tuned;

additional Eisbach combinators and utility methods (by Daniel Matichuck)

fewer messages;

output result messages;

clarified signature;

more position information;

more robust check_state loop, even without session activity (e.g. idempotent use_theories);

synchronized Session.update;

more interruptible use_theories; tuned comments;

clarified exception handling: include interrupts;

support for repeated events;

tuned;

more interruptible; tuned signature;

unload_theories: actually observe required state; misc tuning and clarification;

tuned signature;

prefer typed UUID;

unload_theories after consolidation -- reset node_required; proper node_perspective (amending 0d8e4e777973);

support for "use_theories";

JSON representation for Position.T;

interruptible exploration of dependencies;

tuned signature;

clarified signature;

clarified signature;

tuned message;

proper options;

tuned options;

more comments;

tuned message -- more readable JSON;

more accurate isabelle_id: parent directory is not necessarily at tip;