Allow support for new networks to be added by anybody

[spengrah]

Adding support for a new network means...

• deploying the necessary libraries (e.g. poseiden and other cryptography libraries)
• deploying the reference implementations of the clrfund contracts (e.g. funding round factor, maci factory, registries, etc.)
• deploying the clrfund subgraph(s)

There is a Gnosis tool that enables anybody to deploy all the Gnosis Safe requirements to a new network, including to the same contract addresses. We could use this pattern to deploy all the clrfund requirements to a new network.

This also ideally includes a UI in the deployer app to make it super simple for anybody wanting to deploy clrfund on a new network.

Prereqs out of our control

• The Graph needs to support the network
• EVM network (duh)