Added option to change between contour map and heatmap
Changed max value so that it is calculated on the pixel values and not on the points. This allows for a natural disapation of value in the heatmap example.
Created a separate function to add pixels to the heat value matrix. Makes some operations faster
Fixed bug where max value wasn't reset when heatmap was fundamentally changed
Added two examples to show off heatmap
Updated readme, it references docs that don't exist yet...