Add deploy function to generated Contract type

[glihm]

To ease the deployment of a contract instance, the generated Contract type may expose a deploy function.

abigen!(MyContract, "/path/sierra.json");

fn main() {
    // init provider and account

    let contract_address = MyContract::deploy(...args).await?;
}

The deploy arguments are automatically generated based on the constructor of the contract.

To deploy, we need the class hash. It can be computed compiling the Sierra class, or by taking the Casm class as optional argument.

The deployment is done by the UDC (we may name this function deploy_udc actually), and the parameters of the UDC may be exposed.

The fees must be configurable.
We also want to check if the class hash is already declared. If not, we can skip the deploy with an error.

In the code, this is located in the rs crate here where a new file may be added for this, to be expanded in the contract type here.