Add basic checkbox support to new grids.

Also:

 * Add 'creatable', 'editable' etc. to master view class.
 * Add styles for warning/notice grid rows.
 * Misc. other tweaks.

tailbone/static/js/tailbone.js

@@ -112,11 +112,6 @@ $(function() {
     $('input[type=submit]').button();
     $('input[type=reset]').button();
 
-    /*
-     * Enhance new-style grids.
-     */
-    $('.newgrid-wrapper').gridwrapper();
-
     /*
      * When filter labels are clicked, (un)check the associated checkbox.
      */