Surprise 4.2.4 released

[Sven Schüle]

Hi,

I have released Surprise 4.2.4 on my homepage, with the following changes against 4.2.3:

- Improved move ordering by introducing history heuristic and solving other ordering problems
- Fixed bug in hash table mate scoring which caused Surprise to show very artificial scores and sometimes also to miss the shortest mate
- Slightly reduced code size (8%) by removing some debug-only code which was contained in the release version by accident but was never called

Sven