On branch main

v0.5.13

Changes to be committed:
	new file:   CHANGELOG.md
	new file:   COPYING
	modified:   README.md
	modified:   demo/webviewer_demo.webm
	modified:   funcFiles.go
	modified:   funcWeb.go
	modified:   hdrData.go
	modified:   images/gallery_example.png
	modified:   images/gallery_example_full.png
	modified:   main.go
	modified:   site/index.html
	modified:   site/scripts/main.js
	modified:   site/styles/style.css