message: Update image-smoother.py
diff: # The value in the given matrix is in the range of [0, 255].
  # The length and width of the given matrix are in the range of [1, 150].
  -class Solution(object):
  - def imageSmoother(self, M):
  - """
  - :type M: List[List[int]]
  - :rtype: List[List[int]]
  - """
  - def getGray(M, i, j):
  - directions = [[-1, -1], [0, -1], [1, -1], \
  - [-1, 0], [0, 0], [1, 0], \
  - [-1, 1], [0, 1], [1, 1]]
  -
  - total, count = 0, 0.0
  - for direction in directions:
  - ii, jj = i + direction[0], j + direction[1]
  - if 0 <= ii < len(M) and 0 <= jj < len(M[0]):
  - total += M[ii][jj]
  - count += 1.0
  - return int(total / count)
  -
  - result = [[0 for _ in xrange(len(M[0]))] for _ in xrange(len(M))]
  - for i in xrange(len(M)):
  - for j in xrange(len(M[0])):
  - result[i][j] = getGray(M, i, j);
  - return result
  -# Another solution with getGray function simplified.
  class Solution(object):
  def imageSmoother(self, M):
  """
  