Backend test 3

Chess_jar.jar is a executable that only needs the JVM to run.
ChessFramework.jar only contains the framework and can therefor be used as a library.

Backend test 2

1. Optimized some code
2. Added/ corrected/ updated some docs
3. Number of kings is now irrelevant for (hopefully) all tests. This means that board editors do not have to care about the number of kingss.
4. Fixed a bug that made stalemate possible although the king was checked.
5. Fixed a bug that caused the test for insufficient material to result in true although there was still a queen or a rook on the board.
6. Added 50 moves rule
7. Fixed test for fivefold repetition that always needed an additional move to recognize a repetition.
8. Improved the java interface.
9. Changed order of tests when moving because this might have lead to problems.

Backend test 1

This contains the (at least for now) finished version of the framework. Its purpose is testing for any problems and/or bugs.