update requirements.txt to most recent versions of packages

Author: jakevdp

requirements.txt

@@ -1,13 +1,12 @@
-numpy==1.11.1
-pandas==0.18.1
-scipy==0.17.1
-scikit-learn==0.17.1
-scikit-image==0.12.3
-pillow==3.4.2
-matplotlib==1.5.1
-seaborn==0.7.0
-jupyter
-notebook
+numpy==1.20.1
+pandas==1.2.3
+scipy==1.6.1
+scikit-learn==0.24.1
+scikit-image==0.18.1
+pillow==8.1.2
+matplotlib==3.3.4
+seaborn==0.11.1
+jupyterlab
 line_profiler
 memory_profiler
 numexpr