WIDOCO 1.4.18: Fix javascript issues

This version fixes:

• Minor problems in the generated HTML.
• Minor problems with mixed content in the javascript
• Clarifies documentation on which fields Widoco adopts.

New Contributors

Thanks to:

• @telecsur made their first contribution in #517
• @janvlug made their first contribution in #538
• @HanKruiger made their first contribution in #540
• @JohannesLipp made their first contribution in #547
• @ioggstream made their first contribution in #561

Full Changelog: v1.4.17...v1.4.18