Doc: Update UI Reference Section

### Description
The purpose of the UI Reference section (https://scancode-workbench.readthedocs.io/en/develop/#) is to provide very basic information about each View or Dashboard in the application so that a reader can quickly understand what UI they will see.

We also need to replace the old gif images with simpler "static" png images from a Scan of https://sourceforge.net/projects/e2fsprogs/files/e2fsprogs/v1.45.6/ which is our primary sample/demo project for the current documentation.