Enhance README with DOI badge and links

[carriewright11]

Added DOI badge and updated course material link.

[jhudsl-robot]

Overall readability score: 40.13 (🟢 +0)

File	Readability
README.md	65.63 (🟢 +0)

View detailed metrics

🟢 - Shows an increase in readability
🔴 - Shows a decrease in readability

File	Readability	FRE	GF	ARI	CLI	DCRS
README.md	65.63	61.02	8.85	8.9	11.4	8.39
	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0

Averages:

	Readability	FRE	GF	ARI	CLI	DCRS
Average	40.13	33.68	13.74	15.05	13.72	8.51
	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0	🟢 +0

View metric targets

Metric	Range	Ideal score
Flesch Reading Ease	100 (very easy read) to 0 (extremely difficult read)	60
Gunning Fog	6 (very easy read) to 17 (extremely difficult read)	8 or less
Auto. Read. Index	6 (very easy read) to 14 (extremely difficult read)	8 or less
Coleman Liau Index	6 (very easy read) to 17 (extremely difficult read)	8 or less
Dale-Chall Readability	4.9 (very easy read) to 9.9 (extremely difficult read)	6.9 or less

[github-actions]

OTTR Check Results

Summary

• Spelling check: ✅ PASSED (0 errors found, threshold: 0)
• URL check: ✅ PASSED (0 errors found, threshold: 0)
• Quiz format check: ✅ PASSED (0 errors found, threshold: 0)

🎉 All checks passed!

Last Updated: 2026-10-05-18:29:54

[github-actions]

Re-rendered previews from the latest commit:

• 👀 Quick preview of course website here *
• 🔬 Comprehensive download of the course website here
• Download the .docx file

* note not all html features will be properly displayed in the "quick preview" but it will give you a rough idea.

Updated at 2026-10-05 with changes from the latest commit 6e47ee2