Added user badges and "member since"

added ProBadge, InvestorBadge, DonorBadge components, css
removed "PRO" from appending in display_name
fixes: #50

app/javascript/gabsocial/components/pro_badge.js

@@ -0,0 +1,7 @@
+import React from 'react';
+
+const ProBadge = () => (
+  <span className='badge badge--pro'>Pro</span>
+);
+
+export default ProBadge;