Allow users to re-order epics within their epic board
### Problem to solve
> When facilitating planning at scale across many teams or groups within my organization, I want a high level view of how my epics are moving through a workflow, so that I can track and report on the progress of features and initiatives.
How might we allow users to view an individual epic within their board?
### User experience goal
Individual epics are easy to find within a board, and a user can quickly understand assigned metadata of the epic as well (ie: labels).
### Proposal
Style epic cards similar to issue cards for MVC.

**Figma:** https://www.figma.com/file/epYXyMqBv0LdJ5F2coAMTf/and-2864-Program-boards?node-id=164%3A130
##### Epic card
- These cards include:
- Epic title (wraps to next line if long)
- Labels (wraps to next line if many)
- Identifier (location and number) (truncates similarly to identifiers in the issue board cards)
- Health status (cumulative issue health counts similar to epic tree counts).
- Epic cards can be dragged and dropped similarly to issue cards in a board to reassign list values.
### Documentation
<!-- See the Feature Change Documentation Workflow https://docs.gitlab.com/ee/development/documentation/workflow.html#for-a-product-change
* Add all known Documentation Requirements in this section. See https://docs.gitlab.com/ee/development/documentation/feature-change-workflow.html#documentation-requirements
* If this feature requires changing permissions, update the permissions document. See https://docs.gitlab.com/ee/user/permissions.html -->
### Availability & Testing
<!-- This section needs to be retained and filled in during the workflow planning breakdown phase of this feature proposal, if not earlier.
What risks does this change pose to our availability? How might it affect the quality of the product? What additional test coverage or changes to tests will be needed? Will it require cross-browser testing?
Please list the test areas (unit, integration and end-to-end) that needs to be added or updated to ensure that this feature will work as intended. Please use the list below as guidance.
* Unit test changes
* Integration test changes
* End-to-end test change
See the test engineering planning process and reach out to your counterpart Software Engineer in Test for assistance: https://about.gitlab.com/handbook/engineering/quality/test-engineering/#test-planning -->
### What does success look like, and how can we measure that?
Adopted usage of the health status feature and epics in general.
epic