[third] Patch bootstrap-typeahead to handle objects that aren't strings.

Based on https://github.com/twitter/bootstrap/issues/6579. Doesn't
look like upstream is going to fix that or its 6 duplicates any
time soon.

(imported from commit b3e887d929cc42124aeb1f13abd7503f38f92a1f)

zephyr/static/third/bootstrap/js/bootstrap.js

@@ -1834,7 +1834,7 @@
     constructor: Typeahead
 
   , select: function () {
-      var val = this.$menu.find('.active').attr('data-value')
+      var val = this.$menu.find('.active').data('typeahead-value')
       this.$element
         .val(this.updater(val))
         .change()
@@ -1931,7 +1931,7 @@
       var that = this
 
       items = $(items).map(function (i, item) {
-        i = $(that.options.item).attr('data-value', item)
+        i = $(that.options.item).data('typeahead-value', item)
         i.find('a').html(that.highlighter(item))
         return i[0]
       })