Add wireframe option to eevee and workbench render settings

The ability in 2.8 to have the wireframe visible in the viewport is great. What would be even greater is to introduce a setting within eevee and the workbench rendering modes to render out wireframes.

In addition to having the option available, it would be good to have the ability to control the thickness and the color.

This is different than the wireframe material node as the material node always triangulates faces. It is also different than freestye because it keeps everything fast as opposed to an additional overlay.