Summary
- added ML antiquotation @{master_dir};
- tuned signature;
- more formal references;
- more Haskell antiquotations;
- more Haskell operations;
- support for user-defined Isabelle/Scala command-line tools; misc tuning and clarification;
- replaced some ancient ASCII syntax
- clarified status of legacy input abbreviations
- clarified status of ancient ASCII syntax for big union and inter