(Feature) Deploy ProofOfPhysicalAddress contract/DApp on sokol

[unjapones]

Discuss the posibility to deploy ProofOfPhysicalAddress contract/DApp on sokol.

Expectation

Other POA DApps like poa-dapps-validators can interact with the corresponding contract, and (for example) validators could register and or confirm physical addresses on sokol, so we have real test data. On core, currently the is only one validator with only one confirmed address.

Additional information

• poa-dapps-validators Issue #74 and its PR #75
• If the decision to go on with this is made, create a PR on poa-chain-spec to add the contract's ABI & address to the corresponding branch.

[pablofullana]

@phahulin any steps on how to get this done?