Added #push, #pop, #shift, and #unshift to Point
Added a convenience method for creating translations
Add min, max, and minmax to Annulus
Fixed Point min and max with PointIso, PointOne, and PointZero
Added pop and shift to PointIso, PointOne, and PointZero

push and unshift don't make sense because none of these classes can store arbitrary values
Indentation cleanup