Some minor edits (#3586)
Some minor edits (#3586)

* Some minor edits

I also think it could be cool to explain just a few use cases that answer this question: "Why is GraphQL so cool?"

I also expected to see code examples for image stuff. Also, a random thing about colons that I learned last year is this:

a full sentence must precede the colon :)

* Tweak

danielfarrell/gatsby,mingaldrichgan/gatsby,ChristopherBiscardi/gatsby,0x80/gatsby,gatsbyjs/gatsby,mingaldrichgan/gatsby,gatsbyjs/gatsby,mingaldrichgan/gatsby,danielfarrell/gatsby,gatsbyjs/gatsby,fabrictech/gatsby,0x80/gatsby,gatsbyjs/gatsby,fk/gatsby,fabrictech/gatsby,ChristopherBiscardi/gatsby,gatsbyjs/gatsby,ChristopherBiscardi/gatsby,fk/gatsby,fabrictech/gatsby,danielfarrell/gatsby,gatsbyjs/gatsby,fk/gatsby,ChristopherBiscardi/gatsby,0x80/gatsby