fix "max measure to zero" argument
fix "max measure to zero" argument

Previously it required users (me) prove an impossible fact. Now it just
requires users to prove that when max_measure = S n, eventually all
local measures are <= n.

DistributedComponents/verdi-chord,DistributedComponents/verdi-chord,DistributedComponents/verdi-chord,DistributedComponents/verdi-chord,DistributedComponents/verdi-chord