.org redesign: homepage [design] "hero/above the fold" section

[fk]

• claim with "rotating words" ("Build ______ apps and websites with React") remains
• "Get Started" CTA button stays
  • would like to suggest adding a secondary CTA button "Take the Tutorial" (similar to https://reactjs.org/)
• add a "Gatsby Preview" product teaser
• add newsletter signup form
• thinking about moving the "Used by" section out of the header; def. want to update the logos we show here, and add the possibility of showing more logos

I also want to suggest moving away from the current homepage background design—the 45° roated "Gatsby/rebeccapurple" background shapes.

[marisamorby]

@fk:
Blocked until we decide on messaging. We need to create a new plan after we complete messaging and prototype research.

We will create a new issue once the research is completed and we can work on prototyping.