Generating piece url based on curio multiaddr and contract mapper (#22)

Author: lukasz-wal

.env.example

@@ -1,4 +1,7 @@
 DATABASE_URL=postgres://pguser:pgpassword@localhost:5432/sp_uf
 
 ## LOCAL
-DMOB_DATABASE_URL=postgres://pguser:pgpassword@localhost:5432/sp_uf
+DMOB_DATABASE_URL=postgres://pguser:pgpassword@localhost:5432/sp_uf
+
+# URL for GLIF RPC endpoint
+GLIF_URL=https://api.node.glif.io/rpc/v1