Update libraries to latest versions

requirements.txt

@@ -18,25 +18,25 @@
 #
 # Then install these requirements:
 #     $ pip install --upgrade -r requirements.txt
-# 
+#
 # Finally, start jupyter:
 #     $ jupyter notebook
 #
 
 
 ##### Core scientific packages
 jupyter==1.0.0
-matplotlib==3.0.2
-numpy==1.15.4
-pandas==0.23.4
-scipy==1.2.0
+matplotlib==3.0.3
+numpy==1.16.2
+pandas==0.24.1
+scipy==1.2.1
 
 
 ##### Machine Learning packages
-scikit-learn==0.20.2
+scikit-learn==0.20.3
 
 # Optional: the XGBoost library is only used in the ensemble learning chapter.
-xgboost==0.81
+xgboost==0.82
 
 
 ##### Deep Learning packages
@@ -45,10 +45,8 @@ xgboost==0.81
 # you need a GPU card with CUDA Compute Capability 3.0 or higher support, and
 # you must install CUDA, cuDNN and more: see tensorflow.org for the detailed
 # installation instructions.
-tensorflow==1.12.0
-#tensorflow-gpu==1.12.0
-tensorflow-hub==0.2.0
-tensorflow-probability==0.5.0
+tensorflow==1.13.1
+#tensorflow-gpu==1.13.1
 
 
 # Optional: OpenAI gym is only needed for the Reinforcement Learning chapter.
@@ -60,15 +58,15 @@ tensorflow-probability==0.5.0
 
 
 ##### Image manipulation
-imageio==2.4.1
-Pillow==5.3.0
+imageio==2.5.0
+Pillow==5.4.1
 scikit-image==0.14.2
 
 
 ##### Extra packages (optional)
 
 # Nice utility to diff Jupyter Notebooks.
-nbdime==1.0.4
+#nbdime==1.0.5
 
 # May be useful with Pandas for complex "where" clauses (e.g., Pandas
 # tutorial).
@@ -77,12 +75,8 @@ numexpr==2.6.9
 # Optional: these libraries can be useful in the classification chapter,
 # exercise 4.
 nltk==3.4
-urlextract==0.8.3
-
-# Optional: this extension is handy to easily start/stop tensorboard
-# server(s) directly from Jupyter.
-jupyter-tensorboard==0.1.8
+urlextract==0.9
 
-# Optional: these are useful Jupyter extensions, in particular to display the
-# table of contents
-jupyter-contrib-nbextensions==0.5.0
+# Optional: tqdm displays nice progress bars, ipywidgets for tqdm's notebook support
+tqdm==4.31.1
+ipywidgets==7.4.2