Change to https. (#7277)

* Change to https.

* Revert the py_tf file.

machine_learning/lstm/lstm_prediction.py

@@ -1,7 +1,7 @@
 """
     Create a Long Short Term Memory (LSTM) network model
     An LSTM is a type of Recurrent Neural Network (RNN) as discussed at:
-    * http://colah.github.io/posts/2015-08-Understanding-LSTMs
+    * https://colah.github.io/posts/2015-08-Understanding-LSTMs
     * https://en.wikipedia.org/wiki/Long_short-term_memory
 """
 import numpy as np

machine_learning/sequential_minimum_optimization.py

@@ -28,7 +28,7 @@ Usage:
 Reference:
     https://www.microsoft.com/en-us/research/wp-content/uploads/2016/02/smo-book.pdf
     https://www.microsoft.com/en-us/research/wp-content/uploads/2016/02/tr-98-14.pdf
-    http://web.cs.iastate.edu/~honavar/smo-svm.pdf
+    https://web.cs.iastate.edu/~honavar/smo-svm.pdf
 """
 
 
@@ -43,7 +43,7 @@ from sklearn.datasets import make_blobs, make_circles
 from sklearn.preprocessing import StandardScaler
 
 CANCER_DATASET_URL = (
-    "http://archive.ics.uci.edu/ml/machine-learning-databases/"
+    "https://archive.ics.uci.edu/ml/machine-learning-databases/"
     "breast-cancer-wisconsin/wdbc.data"
 )