CMS-4618 Media Types - Introduce input type FileUploader

- refactored UploadItem<Model>
- refactored api.ui.uploader.Uploader to use new UploadItem
- added onUploadFailed event to Uploader
- deleted api.ui.uploader.FileUploader
- updated api.content.MediaUploader to show links to uploaded items (link is not working yet)
- updated ImageSelector input type to handle upload error
CMS-4597 User Manager - Refresh principals in TreeGrid after updates

Implemented the edit, update and delete events grid handlers.
Merge pull request #1092 from enonic/cms-4618

CMS-4618 Media Types - Introduce input type FileUploader
Merge pull request #1093 from enonic/CMS-4597

CMS-4597 User Manager - Refresh principals in TreeGrid after updates
CMS-4704 Implement basic VHost filter. Not working yet. Just the basic classes.
CMS-4695 TreeGrid - Remove unused animation code

Removed the obsolete animation code from the `TreeGrid`.