remap keword in change_box for elastic constant

for elastic constant, the sample file uses the change_box command without remap keyword.
remaping is not done by default in this command.
I think the code should be modified for the latest version???

Good point. Adding remap does not change the answer significantly, because a minimization is performed after each deformation, but it speeds up the calculation by a factor of 10 or more. I will make that change.