[Misc] Update README(s) (#962)

* Update

* Update

examples/pytorch/cluster_gcn/run_reddit.sh

@@ -2,5 +2,5 @@
 
 
 python cluster_gcn.py --gpu 0 --dataset reddit-self-loop --lr 1e-2 --weight-decay 0.0 --psize 1500 --batch-size 20 \
-  --n-epochs 30 --n-hidden 128 --n-layers 0 --log-every 100 --use-pp --self-loop \
+  --n-epochs 30 --n-hidden 128 --n-layers 1 --log-every 100 --use-pp --self-loop \
   --note self-loop-reddit-non-sym-ly3-pp-cluster-2-2-wd-5e-4 --dropout 0.2 --use-val --normalize

examples/pytorch/dgmg/README.md

 # Learning Deep Generative Models of Graphs
 
 This is an implementation of [Learning Deep Generative Models of Graphs](https://arxiv.org/pdf/1803.03324.pdf) by 
-Yujia Li, Oriol Vinyals, Chris Dyer, Razvan Pascanu, Peter Battaglia. 
+Yujia Li, Oriol Vinyals, Chris Dyer, Razvan Pascanu, Peter Battaglia.
+
+For molecule generation, see 
+[our model zoo for Chemistry](https://github.com/dmlc/dgl/tree/master/examples/pytorch/model_zoo/chem/generative_models/dgmg).
 
 ## Dependencies
 - Python 3.5.2

examples/pytorch/model_zoo/chem/README.md

@@ -21,6 +21,16 @@ Before you proceed, make sure you have installed the dependencies below:
 
 The rest dependencies can be installed with `pip install -r requirements.txt`.
 
+## Speed Reference
+
+Below we provide some reference numbers to show how DGL improves the speed of training models per epoch in seconds.
+
+| Model                      | Original Implementation | DGL Implementation | Improvement |
+| -------------------------- | ----------------------- | ------------------ | ----------- |
+| GCN on Tox21               | 5.5 (DeepChem)          | 1.0                | 5.5x        |
+| AttentiveFP on Aromaticity | 6.0                     | 1.2                | 5x          |
+| JTNN on ZINC               | 1826                    | 743                | 2.5x        |   
+
 ## Property Prediction
 
 To evaluate molecules for drug candidates, we need to know their properties and activities. In practice, this is