Ability to manually link an issue with multiple development branches

Currently:

Current JIRA integration with Bitbucket (and I expect GitHub and/or other DVCSs) allows automatic linking of a JIRA issue with a git branch, provided the issue's key is included in the branch name. Commits are similarly linked if the commit message also includes the issue key, and the Development panel when viewing that issue provides direct links to those branches and/or commits.

Suggested:

As a user I would like to be able to manually link one or more arbitrarily-named branches (i.e. the branch does not need to have the issue key in its name) to an issue. This could occur in a way similar to linking JIRA issues, or an approach like Labels or Components.

Example Use Case:

I tend to name branches with the issue key of an Epic or other large-effort issue. The related work may involve multiple JIRA issues, each of which should be linked to the branch. The reverse is also true – a given Epic or other issue may pertain to (or at least have relevant information regarding) multiple branches, but those branches don't necessarily have every related issue's key in their branch names.

As a workaround, I'm currently using a Custom Field to specify related branches on an issue, specifically a Labels field to try to minimize text discrepancies like typos. Duplicate values still do occur, however, since labels are case-sensitive (e.g. branch names "myfeature-KEY-123" and "myfeature-key-123" and "MyFeature-Key-123" are treated as distinct values). Possibly a drop-down selection (e.g. similar to Project Components) could be available for this field so that links are made to a pre-determined list of known existing branches, or some happy medium.