fix(lists): Removes event list css
fix(lists): Removes event list css

[ReFinishes #95558418]

BREAKING CHANGE: (html) The `.event-list` class is no longer supported.
If you want to build a event list, build it up using a group list. See
an example at http://styleguide.pivotal.io/elements.html#list_group

pivotal-cf/pivotal-ui,pivotal-cf/pivotal-ui,npm/pivotal-ui,CanopyCloud/pivotal-ui,npm/pivotal-ui,sjolicoeur/pivotal-ui,sjolicoeur/pivotal-ui,sjolicoeur/pivotal-ui,CanopyCloud/pivotal-ui,pivotal-cf/pivotal-ui,sjolicoeur/pivotal-ui,npm/pivotal-ui,CanopyCloud/pivotal-ui