Color Viewer Slider Example with Mobile Support

[jongund]

This is an updated version of the slider 1 example for picking a color.

New features include:

1. Javascript file that uses a single prototype object for the example.
2. Use SVG graphics for buttons, thumbs and rail.
3. Improve high contrast support through use of inline SVG graphics.
4. Mobile support with buttons

Preview Link

Color Viewer Slider with mobile support example

Review checklist

• Editorial review by @mcking65
• Functional review by @a11ydoer
• Visual design review by @a11ydoer
• Accessibility review by @charmarkk
• Code review by @spectranaut
• Test review by @spectranaut

NOTE: The Javascript and CSS is the same as the updated color picker example, they share the same CSS and Javascript files

[jongund]

@mcking65
This is the version of the color viewer example with mobile support.
I have updated the accessibility features section.
This example is ready for editorial review.

[jongund]

This pull request is superseded by pull #1746.