Media: Update admin image editor design.

Significant restructure of the admin image editor interface, but no new functionality. Reorganize editing buttons into a common region at the top of the editor. Move image rotation tools into a pop-out menu. Add 180 degree rotation option. Add scale button to control group. Move sidebar tools next to the editing canvas to improve visual proximity between action and result. Enlarge editing canvas and crop handles. Separate activating crop functions from applying crop. Add numeric inputs for crop & scale values. 

A long term goal is to move undo/redo and cancel/save into the modal title bar, but that is not feasible without significant updates to the modal framework.

Props afercia, karmatosed, nrqsnchz, antpb, chaion07, costdev, peterwilsoncc, antpb, sabernhardt, prashantbhivsane, joedolson.
Fixes #50523.

git-svn-id: https://develop.svn.wordpress.org/trunk@55919 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/css/common.css

@@ -191,7 +191,6 @@ p.popular-tags,
 .wp-editor-container,
 .popular-tags,
 .feature-filter,
-.imgedit-group,
 .comment-ays {
 	border: 1px solid #c3c4c7;
 	box-shadow: 0 1px 1px rgba(0, 0, 0, 0.04);
@@ -204,7 +203,6 @@ p.popular-tags,
 .widgets-holder-wrap,
 .popular-tags,
 .feature-filter,
-.imgedit-group,
 .comment-ays {
 	background: #fff;
 }