Montecarlo in general basis IV: Put correct indices to hoft_general,
check that the time_i, time_j ordering is correct and check signs of all
hoft_general. Also, I checked correct placement of hofts into
optical_coherences (does not contain any bras) and not_last_round (no
bra_i, ket_i).

Diagnosis: Everything was OK in the current MCM implementation, except
for four cases that do not appear in optical coherences. They probably
have wrong ordering of time_i/time_j.