[DOC] provide supplementary resources (#326)

* provide supplementary resources

We encourage DL beginners to check out DGL project by providing links on both English and Chinese README :)

https://github.com/diveintodeeplearning/d2l-zh/blob/master/README.md
https://github.com/diveintodeeplearning/d2l-en/blob/master/README.md

* Update README.md

README.md

@@ -145,6 +145,12 @@ For the basics of coding with DGL, please see [DGL basics](https://docs.dgl.ai/t
 
 For more realistic, end-to-end examples, please see [model tutorials](https://docs.dgl.ai/tutorials/models/index.html).
 
+
+## New to Deep Learning?
+
+Check out the open source book [*Dive into Deep Learning*](http://en.diveintodeeplearning.org/).
+
+
 ## Contributing
 
 Please let us know if you encounter a bug or have any suggestions by [filing an issue](https://github.com/dmlc/dgl/issues).
@@ -152,10 +158,12 @@ Please let us know if you encounter a bug or have any suggestions by [filing an
 We welcome all contributions from bug fixes to new features and extensions.
 We expect all contributions discussed in the issue tracker and going through PRs.  Please refer to the PR guide.
 
+
 ## The Team
 
 DGL is developed and maintained by [NYU, NYU Shanghai, AWS Shanghai AI Lab, and AWS MXNet Science Team](https://www.dgl.ai/about).
 
+
 ## License
 
 DGL uses Apache License 2.0.