[Release] Update readme performance number (dmlc#441)

* update README performance number

* news

README.md

@@ -15,11 +15,11 @@ A summary of the model accuracy and training speed with the Pytorch backend (on
 
 | Model | Reported <br> Accuracy | DGL <br> Accuracy | Author's training speed (epoch time) | DGL speed (epoch time) | Improvement |
 | ----- | ----------------- | ------------ | ------------------------------------ | ---------------------- | ----------- |
-| [GCN](https://arxiv.org/abs/1609.02907)   | 81.5% | 81.0% | [0.0051s (TF)](https://github.com/tkipf/gcn) | 0.0042s | 1.17x |
+| [GCN](https://arxiv.org/abs/1609.02907)   | 81.5% | 81.0% | [0.0051s (TF)](https://github.com/tkipf/gcn) | 0.0038s | 1.34x |
 | [SGC](https://arxiv.org/abs/1902.07153) | 81.0% | 81.9% | n/a | 0.0008s | n/a |
 | [TreeLSTM](http://arxiv.org/abs/1503.00075) | 51.0% | 51.72% | [14.02s (DyNet)](https://github.com/clab/dynet/tree/master/examples/treelstm) | 3.18s | 4.3x |
-| [R-GCN <br> (classification)](https://arxiv.org/abs/1703.06103) | 73.23% | 73.53% | [0.2853s (Theano)](https://github.com/tkipf/relational-gcn) | 0.0273s | 10.4x |
-| [R-GCN <br> (link prediction)](https://arxiv.org/abs/1703.06103) | 0.158 | 0.151 | [2.204s (TF)](https://github.com/MichSchli/RelationPrediction) | 0.633s | 3.5x |
+| [R-GCN <br> (classification)](https://arxiv.org/abs/1703.06103) | 73.23% | 73.53% | [0.2853s (Theano)](https://github.com/tkipf/relational-gcn) | 0.0097s | 29.4x |
+| [R-GCN <br> (link prediction)](https://arxiv.org/abs/1703.06103) | 0.158 | 0.151 | [2.204s (TF)](https://github.com/MichSchli/RelationPrediction) | 0.453s | 4.86x |
 | [JTNN](https://arxiv.org/abs/1802.04364) | 96.44% | 96.44% | [1826s (Pytorch)](https://github.com/wengong-jin/icml18-jtnn) | 743s | 2.5x |
 | [LGNN](https://arxiv.org/abs/1705.08415) | 94% | 94% | n/a | 1.45s | n/a |
 | [DGMG](https://arxiv.org/pdf/1803.03324.pdf) | 84% | 90% | n/a | 238s | n/a |
@@ -31,6 +31,11 @@ a model similar to GCN.
 
 We are currently in Beta stage.  More features and improvements are coming.
 
+## News
+
+v0.2 has just been released! Many features, bugfix and performance improvement. See release note
+[here](https://github.com/dmlc/dgl/releases/tag/v0.2).
+
 ## System requirements
 
 DGL should work on