Missing docs for creating custom interpolation

[thomaslombart]

Hey,

I've been diving into the code source of Polyglot lately and have actually found that we can create a custom interpolation syntax by passing an interpolation property to the Polyglot constructor.

I noticed there are no documentation on how to create our own custom interpolation syntax on your docs and wanted to let you know about it.

[thomaslombart]

Actually, there is a documentation on the repo's README file but not on Airbnb's engineering website (https://airbnb.io/polyglot.js/).

[ljharb]

Docs have been updated.

[tomsabin]

@ljharb looks like there's some rendering issues on the airbnb.io/polyglot.js site:

GitHub README	airbnb.io/polyglot.js

notice that on airbnb.io there is only the single character ' instead of '{{'