Display file roles on `show -f`

[n2taylor]

This is an implementation of the Enhancement in #419. My very first Clojure PR!

Description

This change modifies the print-fileset helper to include file roles in the displayed output. The file roles were derived from the fileset directly. If there is a better way to access the file roles, please advise.

Motivation and Context

It's for Issue #419

How Has This Been Tested?

Tested against various Boot projects out in the wild with no issues. Also I cobbled together a toy repo to test against locally (this is not included in the PR). Otherwise there are no automated test changes here.

It has only been tested on Mac OS X.

Screenshots (if appropriate):

Before:

After:

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [x] I have read the CONTRIBUTING document.
• [ ] I have added tests to cover my changes.
• [x] All new and existing tests passed.