Fix the sound issues and crashes on some platforms
This commit updates misc/libphyslayer/physfsrwops.* files to the latest versions
provided by PhysFS project (https://github.com/icculus/physfs/tree/main/extras/).
Directory for automated tests to test the engine.
Run `ctest` in the root directory of this repository to run all tests.
Run `ctest -R <test name>` to run only the test with the given name.
This requires you to have CMake.