Bloodhound 8.4.1 Link Support Overlay

Copy these files over the same paths in your existing Bloodhound installation.

Changed files:
- admin/config.php
- admin/functions.php
- admin/edit_report.php
- admin/new_report.php
- templates/timeline.php
- CHANGELOG.txt
- README.txt

Feature summary:
- Adds a Link toolbar button in New Report and Edit Report.
- Highlight a word or phrase, click Link, and enter a URL.
- If no text is highlighted, Link inserts the URL itself as a clickable link.
- Plain http(s) and www URLs in the report body are converted to live links when saved/displayed.
- Saved links are sanitized to allow http, https, and mailto links only.