Config for Input and Output

[nicolemah99]

First draft example using json format but we could also use yaml/toml/etc...

data_streams.json

{
"output": "/path/to/save/data",
"credentials": {
  "username": "user123",
  "password": "password123"
},
"meters": [{
  "id": "meter_abc_123",
  "ip": "10.10.10.10",
  "type": "SEL735",
}, {
  "id": "meter_abc_124",
  "ip": "10.10.10.11",
  "type": "SEL735",
  // Override the default credentials
  "credentials": {
     "username": "user321",
     "password": "pass321",
  }
}, ....],
}