Replace the welcome jumbotron with a dismissible alert.
Add JQuery Cookies plugin.
Add logic to keep track of dismissed alerts.
Merge branch 'jquery-cookie'

Conflicts:
	src/Premotion.Mansion.Web/Web/Cms/css/cms.css
	src/Premotion.Mansion.Web/Web/Types/CmsHomePlugin/CmsHomePlugin.tpl