Reactify item tags box

Improvements:

- Fixes autocomplete text remaining in field after selection in Fx60
- No more text or icon shifting on select (tested on macOS)

Changes:

- Tags are now selected on mousedown with no active state, as in web
  library

Regressions:

- Tooltip with tag type doesn't appear when hovering over icon
- Pressing Tab after modifying a tag loses focus
- Right-click in textbox shows custom menu instead of default text
  editing context menu (Cut/Copy/Paste)

To-do:

- Switch to this version for note tags box
- Style colored tags in autocomplete drop-down? Sort to top?
- Only show delete button on row hover, as in web library?

resource/require.js

@@ -93,8 +93,10 @@ var require = (function() {
 		id: 'zotero/require',
 		paths: {
 			'': 'resource://zotero/',
+			'containers/': 'chrome://zotero/content/containers/',
 			'components/': 'chrome://zotero/content/components/',
-			'zotero/': 'chrome://zotero/content/modules/'
+			'zotero/': 'chrome://zotero/content/modules/',
+			'@zotero/': 'chrome://zotero/content/modules/'
 		},
 		globals
 	});