Fix menu in mobile nav
Optimize marshall's picture
Change end keynote speaker list
Adjust schedule layout to 10 columns width

* Since the timeline is positioned `relative`-ly, it bleeds out of the
  col-10 box.
Add twitter link and hastag
Fix CSS
Try out config.yml based permalink setup
Revert "Try out config.yml based permalink setup"

This reverts commit cbbca95a613856bc79988a1fcd461decc0f45587.
Use site.url instead of adding links in config.yml