- adds new images to premium feature sections
- fixes side bar view images to be side-by-side
- in the last step of the getting started walkthrough, add image and a button that links to the premium feature walkthrough
- updates the old settings.png image with a new version
- adds a new image of the quick setup
- adds a note about worktrees not working on the web

Moves generated images into dist/webviews/media

Co-authored-by: Eric Amodio <eamodio@gmail.com>

Updates images in README

Updates GitLens logo
Adds CodeStream sponsor

Changes changelog image links to permalinks
Moves all images for docs into a docs folder
Removes unused images