Migrates jquery-ui to npm package

jquery-ui has been updated in the regristry to point to npm:jquery-ui
instead of github:components/jqueryui.

Further, package-overrides that pointed at the github:components version
of both jquery-ui and jquery have been updated to rely on the npm version
of the package.

Fixes #1008

registry.json

@@ -348,7 +348,7 @@
   "jiff": "github:cujojs/jiff",
   "joi": "github:capaj/joi-browser",
   "jquery": "npm:jquery",
-  "jquery-ui": "github:components/jqueryui",
+  "jquery-ui": "npm:jquery-ui",
   "jquery-ui-layout": "github:allpro/layout",
   "jquery-autosize": "github:jackmoore/autosize",
   "jquery-custom-selection": "github:michalstocki/jquery-custom-selection",