This PR contains the work done to include a first version of the Marvel API document specification (that requires further tweaking) and also, the defined how the client would be generated by the Open API library.
Reviewed-on: #2
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>
