Add Safe deployment functionality to Safe class

[dasanra]

Context / issue

Now that it's possible to init the Safe class only using the intended Safe configuration it will also make sense to have in this class the deployment function. Currently it's required to manually create the deployment transaction and also craft the multisend when it's intended to deploy and execute transactions at the same time

Proposed solution

• Move the deploy function from SafeFactory to the Safe class.
• Create a function to deployAndSend transactions.
• Return a new instance of the Safe pointing to the new deployed Safe instead config based only.
• Prevent to call the deployment function if the Safe is already deployed.

Alternatives

• Check for Safe deployment in the normal send transaction removing the need of calling explicitly to a deployment transaction.