Create a Mime Token setup script for testing

[PJColombo]

We could facilitate the integration of the Mime Token into third-party libraries by having a Solidity script for testing that automates the setup and preparation of the Mime Token contract, abstracting the users from the technical details involved, such as creating a Merkle proof from a file, claiming and configuring a set of holders to be used in the tests, instantiating the Mime Token contract itself, etc. This would make the testing process much more streamlined and user-friendly.