Enforce quality of metadata that comes from raw INFO files

## Background
Currently, Enceladus doesn't validate INFO files. It could be helpful for downstream analysis to validate if specific mandatory fields are present and/or in the correct format.

## Feature
Make Standardization refuse to process the data if the provided INFO file does not pass the validation.

## Example [Optional]
* Add validation of the country code field and make sure it has a valid value.
* Add `frequency` field as part of INFO metadata to track how often data is ingested (clarification needed).
* Report date should have a specific format ('yyyy-MM-dd').