Changes

Summary

1. tuned spelling;
2. isabelle update_inner_syntax_cartouches;
3. support for isabelle update -u inner_syntax_cartouches;
4. tuned;
5. isabelle update -u mixfix_cartouches;
6. support for "isabelle update -u mixfix_cartouches";
7. NEWS;
8. tuned signature;
9. tuned output;
10. tuned;
11. tuned;
12. mixfix annotations may use cartouches;
13. tuned;
14. tuned;
15. tuned;
16. tuned signature;
17. clarified signature: more types;
18. tuned;