Minor tweak to twitter tags

Author: leebyron

site/_core/Site.js

@@ -31,12 +31,10 @@ var Site = React.createClass({
           <meta property="og:url" content="http://graphql.org/" />
           <meta property="og:image" content="/img/og_image.png" />
           <meta property="og:image:type" content="image/png" />
-          <meta property="og:image:width" content="1200" />
-          <meta property="og:image:height" content="630" />
           <meta name="twitter:card" content="summary" />
           <meta name="twitter:site" content="@graphql" />
           <meta name="twitter:title" content="GraphQL: A query language for APIs." />
-          <meta name="twitter:description" content="GraphQL gives clients the power to ask for exactly what they need and nothing more, makes it easier to evolve APIs over time, and enables powerful developer tools." />
+          <meta name="twitter:description" content="GraphQL gives clients the power to ask for exactly what they need and nothing more, making it easier to evolve APIs over time." />
           <meta name="twitter:image" content="/img/twitter_image.png" />
           <link rel="shortcut icon" href="/img/favicon.png" />
           <link rel="home" type="application/rss+xml" href="/blog/rss.xml" title="GraphQL Team Blog" />