chore(docs): fix links

doc/index.md

@@ -7,6 +7,6 @@ package is published on [NuGet](https://www.nuget.org/packages/Ipfs.Engine).
 The interplanetary file system is the permanent web. It is a new hypermedia distribution protocol, addressed by content and identities. IPFS enables the creation of completely distributed applications. It aims to make the web faster, safer, and more open.
 
 - [Articles](articles/intro.md) on using the Engine
-- [Engine Documentation](api/Ipfs.Api.yml) describes the core objects in detail  
+- [Engine Documentation](api/Ipfs.Engine.yml) describes the core objects in detail  
 
 [![IPFS Core Engine](https://github.com/ipfs/interface-ipfs-core/raw/master/img/badge.png)](https://github.com/ipfs/interface-ipfs-core)