Generalise string analysis to arbitrary linked lists

Add the functions 'listAnalysis' as a generalisation of 'stringAnalysis'. Add 'listLengthPerConstrAnalysis' and 'listLengthAnalysis' which allow to compute the length of various linked lists on the heap.

These new analysis scripts are useful to find whether you have a few large lists, or many small lists, and gives an estimate to how many infinite lists there are on the heap.