feat: move to compress and decompress route options and typescript improvements

[darkgl0w]

Hello.

Following #198 proposal, this PR aims to :

• add compress and decompress route shorthand configuration properties
• improve typescript types and actually test those types
• update the documentation

Note: some of those changes are breaking changes and will require a major bump.

Checklist

• run npm run test and npm run benchmark
• tests and/or benchmarks are included
• documentation is changed or added
• commit message and code follows the Developer's Certification of Origin
  and the Code of conduct

[darkgl0w]

Previously it was defined as NodeModule, but I don't think it's ok, example :

const zlib = require('zlib')

app.register(fastifyCompress, {
  zlib: zlib // this will trigger a typescript argument error if set to NodeModule
})

unknown is more suited here I think. WDYT ?

[mcollina]

Could you avoid the breaking change? Just document the new way and copy the old option into the new one.

[darkgl0w]

Could you avoid the breaking change? Just document the new way and copy the old option into the new one.

@mcollina > Yes code wise I think I can avoid the breaking change by applying your suggestion and by throwing a deprecation hint warning with typescript (Typescript wise it should be doable, I will try to research a way of tweaking routes config typescript types).
WDYT in the case where someone makes something like this ? Can I go and consider that the new shorthand provided values take precedence on the old ones ? Is it acceptable to you ?

'use strict'
const app: FastifyInstance = fastify()
app.register(require('fastify-compress'), { global: false })
app.get('/', {
  compress: {
    zlib: {
      createGzip: () => createCustomGzipOne() // This one will be the final chosen value. Is it OK ?
    }
  },
  config: {
    compress: {
      zlib: {
        createGzip: () => createCustomGzipTwo()
      }
    }
  }
}, (req, reply) => {
  // ...
})

[mcollina]

The outer one takes precendence.

[darkgl0w]

@mcollina > Oups sorry I made a mistake in my example, I intended to give precedence to the new compress option over the old { config: compress } one ?
Have I guessed correctly or is it the other way around ? :p

[mcollina]

lgtm, this is ok

[mcollina]

lgtm