no issue
- adds `gh-image-uploader` that handles image uploads in a fully ember fashion and with no dependency on `uploader.js`
- adds `gh-image-uploader-with-preview` that can fully replace the old `gh-uploader`
- replace uses of `gh-uploader` in PSM & TSM with `gh-image-uploader-with-preview`
- updates the editor preview image handling to use the new `gh-image-uploader-with-preview` component
- updates the image upload modal to use `gh-image-uploader` (utilises the `saveButton=false` flag which means the preview has to be handled externally to avoid auto-replacement when typing a URL)
- removes all old `uploader.js` related code
- adds custom `RequestEntityTooLargeError` and `UnsupportedMediaTypeError` errors to our `ajax` service
- [x] Mobilemenu button is missing from `content` and `editor` views
- [x] Mobilemenu pane slides entire content over, should expand over-top-of-content
- [x] Mobilemenu can't be closed
- [x] gh-view-title no longer generates an extra div; it is the h2.
- [x] gh-autonav-toggle closes the mobile menu on mobile. renamed `gh-menu-toggle`
- [ ] There is weird behaviour with mobile menu when changing from big=>small=>big viewport sizes
- ~~[ ] (Future issue) Ghost should remember (localstorage?) whether desktop menu is expanded or collapsed~~
- Adds gh-view-title component to implement mobile menu button for titles on any page
- Refactors the `content-cover` out into the application template
- Fix various z-index issues with content-cover and gh-alert
- Move `.settings-menu-expanded` application view state from body to `.gh-viewport`
- Unify nav menu / mobile menu actions and code
