Diagonal Grow

Given the size of 2D matrix (width and height). You have to fill it like this...

4 5 6 7 3 4 5 6 2 3 4 5 1 2 3 4

**Input: ** Two arguments. Width and height of future matrix

**Output: ** numpy array

**Example:**

diagonal_grow(3, 3) == np.array([ [3,4,5], [2,3,4], [1,2,3] ]) diagonal_grow(2,4) == np.array([ [4,5], [3,4], [2,3], [1,2] ])