Add support for link types

[cristian]

@Emile

Double brackets makes sense, but I think licat mentioned that it’s currently not recognized as a link.

True, it’s not recognized.
You cannot ctrl+link inside the note

@Emile

And using entities as properties may sound a bit confusing: It’d be both a node in the graph and an edge. And not so sure what the use would be for this? As long as you can query all has ingredients relations.

I was thinking about describing the properties themselves, which is useful when your Personal Wiki is a mix of Wiki and Database.

But now that you say it, it’s confusing. Also, Front matter is already defined as YAML or TOML. (do they allow double brackets [] ?)