IV Exercises: Part 1/7 - WarmUpExercise.m

Signed-off-by: Yi Zou <yi.zou.linux@gmail.com>
IV Exercises: Part 2/7 plotData and computeCost

Signed-off-by: Yi Zou <yi.zou.linux@gmail.com>
IV Exercises: Part 3/7 Gradient descent for one variable

Signed-off-by: Yi Zou <yi.zou.linux@gmail.com>