* @class Roo.bootstrap.ButtonGroup
* @extends Roo.bootstrap.Component
* Bootstrap ButtonGroup class
+ * @children Roo.bootstrap.Button Roo.bootstrap.form.Form
+ *
* @cfg {String} size lg | sm | xs (default empty normal)
* @cfg {String} align vertical | justified (default none)
* @cfg {String} direction up | down (default down)