feat: adds support for fastify

[sebacruz]

I am trying to add support for fastify but i'm just starting to use this package. Are there any other files that I need to modify?

[tzellman]

@sebacruz Thanks for the PR! I'll pull it down and take a look - we may need to make express and fastify peer dependencies in order to not require apps to be dependent on both.

[tzellman]

The project currently uses the LTS version of node (defined in the .nvmrc file). We'll have to update the PR to use that version so that the lock file doesn't use version 2.

[tzellman]

The jsonapiRequestHolder that is added to the request object is only available as an extension to the Express.Request interface.. I am pretty confident we will need to make some more changes to the middleware and exception-filter in order to get this to work properly with fastify.

Additionally, we will want to orchestrate the test suite so that both express and fastify are tested against. I'll need to dig in a little to see how this would make the most sense to do. 👍

[sebacruz]

@tzellman thank you for you review.

I've already been working on changes that you suggested, can you confirm that they are ok?