[Dijkstra] Implemented an dijkstra shortest path algorithm.
[IPython] added ipython notebook which documents the dijkstra algorithm.
[Algorithms] Added some helper functions to make the implemetnation of the minimumspantree algorithm easier.
[Algorithms] Added the minimum span tree algorithm.
[Ipython Notebook] Added proof of minimum span tree implementation.
Fixed some tests not running through. Wrote Tests for the minimum span tree definition.
[IPython] MiminumSpanTree - added additional proof