Change prop from className to class (#5)

Author: nuc

src/__tests__/components/Image-test.js

@@ -17,7 +17,7 @@ describe('Image', () => {
       layout: 'responsive',
       width: '100',
       height: '100',
-      className: 'such-a-class'
+      class: 'such-a-class'
     }
     const image = renderComponent(<Image {...props} />)
     expect(image.toJSON().props).toMatchObject(props)
@@ -31,7 +31,7 @@ describe('Image', () => {
       layout: 'responsive',
       width: '100',
       height: '100',
-      className: 'such-a-class'
+      class: 'such-a-class'
     }
     const invalidProps = {
       randomStuff: 'aiosdo',

src/__tests__/components/__snapshots__/Carousel-test.js.snap

@@ -13,7 +13,7 @@ Array [
 exports[`Carousel matches the snapshot 1`] = `
 <amp-carousel
   autoplay={null}
-  className={undefined}
+  class={undefined}
   delay={null}
   fallback={undefined}
   height="250"

src/__tests__/components/__snapshots__/Image-test.js.snap

@@ -1,11 +1,11 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`[object Object] 1`] = `"<amp-img layout=\\"responsive\\" width=\\"100\\" height=\\"100\\" className=\\"such-a-class\\" src=\\"https://placekitten.com/200/300\\" srcset=\\"/img/amp.jpg 1080w, /img/amp-900.jpg 900w\\" alt=\\"just an alt\\"></amp-img>"`;
+exports[`[object Object] 1`] = `"<amp-img layout=\\"responsive\\" width=\\"100\\" height=\\"100\\" class=\\"such-a-class\\" src=\\"https://placekitten.com/200/300\\" srcset=\\"/img/amp.jpg 1080w, /img/amp-900.jpg 900w\\" alt=\\"just an alt\\"></amp-img>"`;
 
 exports[`Image matches the snapshot 1`] = `
 <amp-img
   alt=""
-  className={undefined}
+  class={undefined}
   fallback={undefined}
   height={undefined}
   heights={undefined}

src/__tests__/components/__snapshots__/Sidebar-test.js.snap

@@ -12,7 +12,7 @@ Array [
 
 exports[`Sidebar matches the snapshot 1`] = `
 <amp-sidebar
-  className={undefined}
+  class={undefined}
   fallback={undefined}
   height={undefined}
   heights={undefined}

src/components/commonPropTypes.js

@@ -18,7 +18,7 @@ const commonPropTypes = {
   width: string,
   height: string,
   fallback: object,
-  className: string
+  class: string
 }
 
 export default commonPropTypes