docs: update ipld example

Author: daviddias

examples/traverse-ipld-graphs/README.md

@@ -1,17 +1,24 @@
 Resolve through IPLD graphs with the dag API
 ============================================
 
-In this set of examples, you can find snippets of code to:
+IPLD stands for [`InterPlanetary Linked-Data`](https://ipld.io/), it is the data model of the content-addressable web. It gives IPFS the ability to resolve through any kind of content-addressed graph, as long as the [adapter for the format is available](https://github.com/ipld/interface-ipld-format#modules-that-implement-the-interface).
 
-- [create nodes of a graph](./put.js)
-- [retrieve a graph node](./get.js)
-- [resolve a path in a graph](./get-path.js)
-- [resolve through graphs of different kind](./get-path-accross-formats.js)
-- [explore a graph with the .tree](./tree.js)
-- [traverse through a slice of the ethereum blockchain](./eth.js)
+This tutorial goes through several operations over IPLD graphs using the [DAG API](https://github.com/ipfs/interface-ipfs-core/tree/master/API/dag).
 
-### Video of the demos
+## [create nodes to build a graph](./put.js)
 
-You can find a video with a walkthrough of this examples on Youtube:
+## [retrieve a node from a graph](./get.js)
 
-- [IPFS DAG API Preview](https://youtu.be/drULwJ_ZDRQ?t=1m29s)
+## [resolve a path in a graph](./get-path.js)
+
+## [resolve through graphs of different kind](./get-path-accross-formats.js)
+
+## [explore a graph with the .tree](./tree.js)
+
+## [traverse through a slice of the ethereum blockchain](./eth.js)
+
+## Video of the demos
+
+Find a video with a walkthrough of this examples on Youtube:
+
+[![](https://ipfs.io/ipfs/QmYkeiPtVTR8TdgBNa4u46RvjfnbUFUxSDdb8BqDpqDEer)](https://youtu.be/drULwJ_ZDRQ?t=1m29s)