Work in progress!

python clone of David Avis and Komei Fukudas http://cgm.cs.mcgill.ca/%7Eavis/C/lrslib/USERGUIDE.html. Added functionality, namely enabling lrs for hyperplane arrangements through a criss-cross pivot rule (an adapted bland pivot rule is also WIP). Furthermore I have added the possibility of a bounding box to restrict pivoting to inside the box.