Changes

Changes from Mercurial (hg https://isabelle.in.tum.de/repos/isabelle/ default)

Summary

1. merged
2. enforce rebuild of Isabelle/ML;
3. clarified signature;
4. Base64: proper support for large Bytes, with subtle change of types (Bytes instead of String);
5. tuned: prefer Bytes operations;
6. unused;
7. proper treatment of long message blocks;
8. clarified sizes;
9. more scalable stream read operations;
10. minor performance tuning;
11. tuned;
12. tuned module structure;
13. tuned names;
14. imitate internal policy of ByteArrayOutputStream: capacity is doubled after first push;
15. tuned whitespace;
16. unused;
17. Bytes.Builder is unsynchronized, like java.io.OutputBuffer;
18. notable performance tuning: avoid overhead of higher-order functions;
19. more efficient equals: avoid somewhat slow sha1_digest (see also 29b761e290c5, 306f273c91ec);
20. more scalable compression, using Bytes.Builder.Stream;
21. tuned: more uniform, less ambitious;
22. tuned;
23. minor performance tuning;
24. minor performance tuning; clarified signature;
25. minor performance tuning;
26. clarified signature;
27. tuned;
28. tuned;
29. clarified signature;
30. minor performance tuning;
31. support large byte arrays, using multiple "chunks"; support incremental builder; clarified "limit" (valid >= 0) vs. "hint" (valid > 0); clarified byte access: prefer unchecked acces and iterators internally;
32. clarified File.eq_content, following 306f273c91ec;
33. tuned;
34. clarified hash and equality: depend on sha1 digest to be collision-free;
35. clarified signature;
36. tuned source structure;
37. tuned signature;
38. minor performance tuning;
39. proper sha1_digest: need to include offset + length;
40. clarified signature: pro-forma support for Bytes with size: Long;
41. minor performance tuning;
42. clarified signature (again);
43. tuned;
44. clarified signature: discontinue somewhat misleading Bytes <: CharSequence;
45. minor performance tuning;
46. clarified signature: more accurate types;
47. clarified signature;