First cut at mobile page

Looks terrible, but the skeleton is there. I'm gonna work on making it
look good, @bellkev offered to get the copy updated
First pass at styling

Basically working, need lots of margins and paddings and things.
Get mobile landing page basically looking right
Add initial landing copy
More copy changes
Get everything looking pretty solid

Still a little wonky on reawlly small screens, but getting very close.
Merge branch 'mobile-landing-pages' of github.com:circleci/frontend-private into mobile-landing-pages

Conflicts:
	src-cljs/frontend/components/mobile.cljs
Swap in svgs in place of pngs
Tweaks for full copy
Merge in upstream changes
Merge branch 'mobile-landing-pages' of github.com:circleci/frontend-private into mobile-landing-pages
Fix header, add links to docs
Better scope for link styling
Merge pull request #50 from circleci/mobile-landing-pages

First cut at mobile page