Fixes #227 - Update NuxtJS instructions

[fabiofdsantos]

Update the instructions to use this plugin in NuxtJS as stated here. I've tested it myself.

(credits: @renzosunico)

[robinvdvleuten]

Thanks for your PR! Are you sure this is the correct way to use this? I am not a Nuxtjs user myself and can't validate this myself.

[fabiofdsantos]

@robinvdvleuten
Here's is an alternative confirmed by NuxtJS maintainers: nuxt/nuxt#3031 (comment)

There's no need to use onNuxtReady. The post only makes a suggestion to bypass Webpack Hot Module Replacement (HMR) (if you are using it for development purposes).

So, by default the configuration should be without onNuxtReady. I've validated it in development & production for NuxtJS v2.12.2 (released on March 31).

[robinvdvleuten]

@fabiofdsantos thank you for checking it and confirming!

[robinvdvleuten]

@all-contributors please add @fabiofdsantos for doc

[allcontributors]

@robinvdvleuten

I've put up a pull request to add @fabiofdsantos! 🎉