message: changed typo in doc (diag --> dgm), used integer for order and internal p, simplify th ecode
diff: @@ -36,10 +36,10 @@ Note that persistence diagrams must be submitted as (n x 2) numpy arrays and mus
  import gudhi.wasserstein
  import numpy as np
  - diag1 = np.array([[2.7, 3.7],[9.6, 14.],[34.2, 34.974]])
  - diag2 = np.array([[2.8, 4.45],[9.5, 14.1]])
  + dgm1 = np.array([[2.7, 3.7],[9.6, 14.],[34.2, 34.974]])
  + dgm2 = np.array([[2.8, 4.45],[9.5, 14.1]])
  - message = "Wasserstein distance value = " + '%.2f' % gudhi.wasserstein.wasserstein_distance(diag1, diag2, order=1., internal_p=2.)
  + message = "Wasserstein distance value = " + '%.2f' % gudhi.wasserstein.wasserstein_distance(dgm1, dgm2, order=1., internal_p=2.)
  print(message)
  The output is:
  @@ -60,12 +60,12 @@ An index of -1 represents the diagonal.
  dgm1 = np.array([[2.7, 3.7],[9.6, 14.],[34.2, 34.974]])
  dgm2 = np.array([[2.8, 4.45], [5, 6], [9.5, 14.1]])
  - cost, matchings = gudhi.wasserstein.wasserstein_distance(diag1, diag2, matching=True, order=1., internal_p=2.)
  + cost, matchings = gudhi.wasserstein.wasserstein_distance(dgm1, dgm2, matching=True, order=1, internal_p=2)
  message_cost = "Wasserstein distance value = %.2f" %cost
  print(message_cost)
  - dgm1_to_diagonal = matchings[np.where(matchings[:,0] == -1)][:,1]
  - dgm2_to_diagonal = matchings[np.where(matchings[:,1] == -1)][:,0]
  + dgm1_to_diagonal = matching[matching[:,0] == -1, 1]
  + dgm2_to_diagonal = matching[matching[:,1] == -1, 0]
  off_diagonal_match = np.delete(matchings, np.where(matchings == -1)[0], axis=0)
  for i,j in off_diagonal_match:
  