simplify show/hide footer and header
header and footer working for profile and infopages
featured and supported icons line up at bottom
clean out footer.

not done yet, needs shorter+wider versions of funder logos.
adds supported-by badges on right of footer
center the tagline stuff on landing page.
signup form looks decent.
signup button triggers test function
basic validation on signup form
mints unique slugs for non-unique firstname/lastname combos.
signup asks user for new email if it's taken
landing page top part is always exact height of viewport.
rename user.as_dict() to dict_about()
add products count to user about_dict
remove Tips service, since we're not using it no more.
tour start modal works.
rips out the tour popover, just modal now.
add test page version to body class
AB testing link to Carl's profile on landing page
login link has higher z-index