Add DocumenterInterLinks.jl in sharing/documentation (#92)

sharing/index.md

@@ -218,8 +218,11 @@ The only thing left to do is to [select the `gh-pages` branch as source](https:/
 
 \advanced{
 
-[DocumenterCitations.jl](https://github.com/JuliaDocs/DocumenterCitations.jl) allows you to insert citations inside the documentation website from a BibTex file.
+You may find the following Documenter plugins useful:
 
+1. [DocumenterCitations.jl](https://github.com/JuliaDocs/DocumenterCitations.jl) allows you to insert citations inside the documentation website from a BibTex file.
+2. [DocumenterInterLinks.jl](https://github.com/JuliaDocs/DocumenterInterLinks.jl) allow you to cross-reference external documentations (Documenter and Sphinx).
+
 Assuming you are looking for an alternative to Documenter.jl, you can try out [Pollen.jl](https://github.com/lorenzoh/Pollen.jl).
 In another category, [Replay.jl](https://github.com/AtelierArith/Replay.jl) allows you to replay instructions entered into your terminal as an ASCII video, which is nice for tutorials.