Bug-zapping

* Corrected the distance fitness calculation (affecting nrg_fit too).
The base position of the stance leg needed to be reset.
* Added the fitness calculation code to RunSeq, so the genome's fitness
is shown after it's run.
* The algorithm produces good results for the specified controller
structure.
** TO-DO ** : Check what happens to each fitness if the model converges
before reaching Tend. Add fitness for Poincare Map eigenvalues.