Resolve "EigenSolver = plan is broken and gives a segmentation fault"
Revert an old commit that changed the window size to the states block size. This is a problem if the states block size is larger than half the Krylov subspace which is hardcoded to 15. By reverting to a window size to 5, this is fixed again.
- I have checked that my code follows the Octopus coding standards
- I have added tests for all the new features added in this request.
Closes #67 (closed)