Setting to save development artifacts and store them in a map

[matnad]

What I did

• Add a setting to save deployment artifacts in development networks
• Add a deployment map that keeps track of deployed contracts, sorted by time

closes #576

How I did it

Save deployment artifacts for development networks at build/deployments/dev/
Maintain a deployment map (of all deployments) at build/depoyments/map.json in the form of

{
  "chainid": { 
    "contractName": [
      "contract address 1", 
      "contract address 2"
    ]
  }

How to verify it

• Deploy a contract and check build/deployments
• I wrote tests for this PR

Checklist

• I have confirmed that my PR passes all linting checks
• I have included test cases
• I have updated the documentation
• I have added an entry to the changelog

[iamdefinitelyahuman]

Looks really good overall! A few nit-picks but nothing major.

[iamdefinitelyahuman]

Great job on this.

[iamdefinitelyahuman]

Suggested change

	::
	.. code-block:: json

I'm not 100% on if json works - but definitely could be python or javascript - just to ensure proper code highlighting.