Finish up retry and log messages in excite_top_triv().
Add a B overlap method that deals with non-gauge-fixed B.
Use it in CG code.
Add tolerance option to calc_PPinv.
Clean up B_overlap and fix the completely non-gauge-fixed case.
Update CG for nw B_overlap. Also use limited precision.
Fix an error case in CG.
Missing part of CG modifications.
Split out connected vector calculation from B_overlap and clean it up.
Attempt to implement B_to_B_GF(). Not yet working properly.
Extend B_overlap to block excitations. Nonzero momentum not yet correct. Cythonized tdvp_common not yet updated.
Working B_to_B_GF(). There's a problem with overlap with no gauge fixing.
Cleaned up tests a lot.
Add optional returning of x to calc_B().