Add support for vyper json input

We should add support to the upcoming json input format for Vyper: https://github.com/ethereum/vyper/pull/1594

It is similar to the solc json input for which we recently added the support: https://github.com/crytic/crytic-compile/pull/29

We need some internal discussions on how to handle best these extensions of existing platforms (`solc` versus `solc_standard_json`, and `vyper` versus the platform to handle this new input)