Add keyboard option to carousel

Also adds unit tests for keyboard events.

Fixes #14468.

js/carousel.js

@@ -14,7 +14,7 @@
   // =========================
 
   var Carousel = function (element, options) {
-    this.$element    = $(element).on('keydown.bs.carousel', $.proxy(this.keydown, this))
+    this.$element    = $(element)
     this.$indicators = this.$element.find('.carousel-indicators')
     this.options     = options
     this.paused      =
@@ -23,6 +23,8 @@
     this.$active     =
     this.$items      = null
 
+    this.options.keyboard && this.$element.on('keydown.bs.carousel', $.proxy(this.keydown, this))
+
     this.options.pause == 'hover' && !('ontouchstart' in document.documentElement) && this.$element
       .on('mouseenter.bs.carousel', $.proxy(this.pause, this))
       .on('mouseleave.bs.carousel', $.proxy(this.cycle, this))
@@ -35,7 +37,8 @@
   Carousel.DEFAULTS = {
     interval: 5000,
     pause: 'hover',
-    wrap: true
+    wrap: true,
+    keyboard: true
   }
 
   Carousel.prototype.keydown = function (e) {