code checking: compiler invocation happens in same directory as generated file -- avoid problem with different path representations on cygwin

Quotient Package: dont unfold mem_def, use rsp and prs instead

Quotient Package: added respectfulness and preservation lemmas for mem.

quotient package: added a list of pre-simplification rules for Ball, Bex and mem

quotient package: lemmas to be lifted and descended can be pre-simplified

merged

renamed class/constant eq to equal; tuned some instantiations

improved deresolving of implicits

Document_View.text_area_extension: do not insist in crashing if (weak) assertion is violated;

Isabelle/jEdit property for global tooltip dismiss delay;

External_Hyperlink: proper error dialog;

Document_Mode.Line_Context: proper semantic equality/hash code avoids memory leak due to interning in org.gjt.sp.jedit.syntax.TokenMarker;

JEDIT_JAVA_OPTIONS: actors.enableForkJoin=false is supposed to enable ResizableThreadPoolScheduler, to avoid starvation of excessive amounts of future tasks etc.;

session_actor: ignore spurious TIMEOUT (again) -- probably stemming from earlier use of receiveWithin;

session_actor: await state assigment of previous change before signalling current change, and avoid crash in overrun situations;

use Future.get_finished where this is the intended meaning -- prefer immediate crash over deadlock due to promises that are never fulfilled; clarified session signalling;

Swing_Thread.now: volatile result to make double-sure;

Document_Model.token_marker: misc tuning and simplification;

added Document.Snapshot.select_markup, which includes command iteration, range conversion etc.; Markup_Tree.select: plain Iterator; misc tuning and simplification;

XML.Cache: intern property keys once and for all (again);

more careful locking of jEdit buffer;

avoid application crash due to wrong requirement -- result is joined, but change not necessarily finished due to extra map;

include Document.History in Document.State -- just one universal session state maintained by main actor; Session.command_change_buffer: thread actor ensures asynchronous dispatch; misc tuning;

volatile variables (in Scala);

non-critical output primitives -- depending on thread-safe TextIO, while races wrt. flushing should not matter;

modernized specifications;

discontinued separate Pure-ProofGeneral keywords session -- protocol commands are already defined in Pure;

discontinued broken no_warnings_CRITICAL -- global output channels must not be changed after startup initialization;

eliminated broken Output.no_warnings_CRITICAL -- context visibility does the job; modernized attribute setup;

more careful treatment of context visibility flag wrt. spurious warnings; misc tuning;