Allow the use of "Integration" fields in Report calculated field formulas

Currently, integration fields like "Rally formatted_id" cannot be used within a formula for report calculated fields. This is limiting since it means we need to create a custom field to be based on these fields to use within the formulas. Consider allowing these fields to be used in the formulas.

Use Case:

Would like to create a report with a calculated field that assesses a status of an epic, and one of the statuses is whether or not the epic has been integrated with Rally. However, the formula syntax doesn't allow me to select any of the integration fields (e.g., Rally formatted_id) to check on them.