Molecule trace x, y, z coordinates

[SylviaWhittle]

It would be good to output statistics for the z-height of the molecule traces from dnatracing. Probably as part of a csv file? This might mean that a new csv file has to be made to hold all the trace coordinates.

[ns-rse]

JSON might be more succinct, will tag this onto #183 as it should be done under the refactored framework rather than the current module.

[ns-rse]

#595 is a duplicate.

CSV is probably a better solution as it would be easier for more people to work with.