docs: update community info with channel links (#2403)

website/src/components/docsearch.js

@@ -24,10 +24,10 @@ class DocSearch extends Component {
     }
 
     return (
-      <a className="utility-input">
-        <img src={searchIcon} />
+      <div className="utility-input">
+        <img src={searchIcon} alt="" />
         <input type="search" placeholder="Search the docs" className="algolia-search" />
-      </a>
+      </div>
     );
   }
 }

website/src/components/header.js

@@ -55,7 +55,7 @@ class Header extends Component {
               <div className="contained">
                 <div className="logo-container">
                   <Link to="/" className="logo">
-                    <img src={logo} />
+                    <img src={logo} alt="Netlify CMS" />
                   </Link>
                   <DocSearch />
                 </div>

website/src/components/video-embed.js

@@ -36,20 +36,23 @@ class VideoEmbed extends Component {
         frameBorder={0}
         allow="autoplay; encrypted-media"
         allowFullScreen
+        title="video_embed"
       />
     );
 
-    const imgPlaceholder = <img src={screenshotEditor} className="responsive" />;
+    const imgPlaceholder = (
+      <img src={screenshotEditor} className="responsive" alt="editor video screenshot" />
+    );
 
     return (
-      <a className="hero-graphic" onClick={this.toggleVideo}>
+      <div className="hero-graphic" onClick={this.toggleVideo}>
         {toggled ? embedcode : imgPlaceholder}
         {!toggled && (
           <div className="hero-videolink">
             <PlayIcon className="hero-videolink-arrow" />
           </div>
         )}
-      </a>
+      </div>
     );
   }
 }