Match formatting of plugin-request.md to bug_report.md , make p-r.md more descriptive, and add a new line at the end of b_r.md

[gregk-git]

This PR:

1. Updates plugin-request.md to match formatting of bug_report.md
2. Makes plugin-request.md more descriptive
3. Adds a new line at the end of bug_report.md, because that was how you had it previously but in my last commit to bug_report.md I forgot to make a new line at the end after my changes.