added requirements.txt

requirements.txt

+absl-py==0.7.0
+astor==0.7.1
+editdistance==0.5.2
+gast==0.2.2
+grpcio==1.18.0
+h5py==2.9.0
+Keras-Applications==1.0.7
+Keras-Preprocessing==1.0.8
+Markdown==3.0.1
+numpy==1.16.1
+opencv-python==4.0.0.21
+pkg-resources==0.0.0
+protobuf==3.6.1
+six==1.12.0
+tensorboard==1.12.2
+tensorflow==1.12.0
+termcolor==1.1.0
+Werkzeug==0.14.1