[Encointer] a fix and new pallets offline-payment and reputation-rings

[brenzi]

This PR introduces new features and a fix for Encointer:

medium-urgent fix:

• fix community treasury stablecoin swap option enactment, (replacing [encointer] fix enactment of approved swap options sigurpol/runtimes#7)

new features:

• enable payments while offline, settle later when online. docs, code

  • Our community in Tanzania has recently suffered a internet shutdown for several days. This prepares us for the next temporary outage.
  • Based on ZK e-cash Groth16 proofs (arkworks)

• enable anonymous proof-of-personhood. docs, code

  • Based on ring-VRF (similar but different from people registry design).

• await benchmark bot

[clangenb]

/cmd bench --runtime encointer-kusama --pallet pallet_encointer_offline_payment pallet_encointer_reputation_rings

[clangenb]

Looks good to me, kicked off the benchmarks.

[github-actions]

Command "bench --runtime encointer-kusama --pallet pallet_encointer_offline_payment pallet_encointer_reputation_rings" has started 🚀 See logs here

[github-actions]

Command "bench --runtime encointer-kusama --pallet pallet_encointer_offline_payment pallet_encointer_reputation_rings" has failed ❌! See logs here

[github-actions]

Review required! Latest push from author must always be reviewed

[clangenb]

/cmd bench --runtime encointer-kusama --pallet pallet_encointer_offline_payment pallet_encointer_reputation_rings

[clangenb]

Benchmark fix LGTM

[github-actions]

Command "bench --runtime encointer-kusama --pallet pallet_encointer_offline_payment pallet_encointer_reputation_rings" has started 🚀 See logs here

[github-actions]

Command "bench --runtime encointer-kusama --pallet pallet_encointer_offline_payment pallet_encointer_reputation_rings" has failed ❌! See logs here