Consequently, 1hz eql m-values were wrong: m=3 instead of m=4 etc.
m=12 contained the values of intabs instead. The current fix is more
robust too.

improved robustness in general

This reverts commit 05feb291.

updated tests and test coverage for zipchunks

refer to python environment on cluster

prepost.simchunks: rename chunk_ into chnk_ so it fits the max char length for job name on PBS qstat