Kidney CA model. Here have now added some extra elements to the parameter vector v_parameters, which allow for a choice of how mesenchyme cells are moved out of the way. Option 1 is normal random selection of target for mesenchyme cells. 2 is probabilistically choose a mesenchyme target cell in accordance to the direction in which the mesenchyme was pushed. Working_file7 also has started to use JPF's suggestion of looking at medial axis, for counting the number of branches.