Support mapping tags to JIRA multicheckboxes

Problem Overview

It is possible to bi-directionally map tags in Aha! with custom multicheckboxes in Jira.

However, it is not possible to configure how the values should map on each side.

This creates errors when the two fields attempt to sync.

Proposed Solution

Allow for this mapping but require that tag and checkbox field values are mapped via the standard Configure modal.

Existing tags are mappable to existing checkboxes.