Update the ceremonies locations storage of the community pallet in the enclave

[echevrier]

The ceremonies locations are in the community pallet : https://github.com/encointer/pallets/blob/f859dff21f9c9fd3863f6eaa5cf64cd1f827c7af/communities/src/lib.rs#L381 The update the locations with get_storage_hashes_to_update method we need the geohash, which is not available.

[echevrier]

Update the locations values in the enclave calling the extrinsic https://github.com/encointer/pallets/blob/f859dff21f9c9fd3863f6eaa5cf64cd1f827c7af/communities/src/lib.rs#L152 -> add a trusted call communities_add_location

[echevrier]

Doen in https://github.com/encointer/community-sidechain/pull/34