* Admin UI update basics
Added the basics for the Admin UI/style update. Very far from being done...
* Admin style updates
- exploring menu
- enabling full width content (integrations selection bg)
- updated main screens
no issue
- email analytics feature has a potential to be resource-intensive so it may be switched off via config, when this is the case we don't want to show stats in the admin that are out of date or won't be added/updated
- fixed page link titles saying "Edit this post" instead of "Edit this page"
no issue
- added "Sends" and "Opens" columns to the posts list to see newsletter performance at a glance
- "Sends" will show the type of members sent to (free, paid, all) as a tooltip
- "Opens" shows open rate by default and total opens on hover
no issue
- moved `primaryTag` CP into the post model as per `primaryAuthor`
- removed all unnecessary or unused CPs in the component's backing class
- switched to using `@post` for direct argument access rather than `this.post`
no issue
Keeps component JS backing files and template files in the same directory which avoids hunting across directories when working with components. Also lets you see all components when looking at one directory, whereas previously template-only or js-only components may not have been obvious without looking at both directories.
- ran [codemod](https://github.com/ember-codemods/ember-component-template-colocation-migrator/) for app-level components
- manually moved in-repo-addon component templates in `lib/koenig-editor`
- removed all explicit `layout` imports as JS/template associations are now made at build-time removing the need for them
- updated `.embercli` to default to new flat component structure
