Include material about High-Dimensional Spaces

[stefansavev]

One of the most important lessons in machine learning and deep learning is how the algorithms navigate in very high-dimensional spaces. Curse of dimensionality == high dimensional spaces. Once you know that you have a very good intuition what's going on. Its very rarely talked in books, but some do (Ravi Kannan has one). I would argue that you need more geometrical intuition than calculus.