Rename fastify instance to app

[Eomm]

🚀 Feature Proposal

As followup
fastify/website#259

Motivation

Better naming convention

[hionnode]

Can I take up this issue...

[zekth]

Can I take up this issue...

Go for it

[hionnode]

Just a doubt, should I fork the repo, or push a feature branch

[climba03003]

Just a doubt, should I fork the repo, or push a feature branch

Fork it and make a branch on your fork
You cannot push a feature branch here without permission.

[dancastillo]

@Eomm is this still an issue? I see instance being used on fastify docs here

[Eomm]

@Eomm is this still an issue? I see instance being used on fastify docs here

I was thing about from:

fastify.addSchema()

to:

app.addSchema()

But there are many things that are not mapped yet. I use a lot this snippet repo ffhello saves me a lot to help people debug little things