material icons for core types

note that this switch logic should probably be moved outside into some sort of config file

src/components/presentational/CardSource.js

@@ -5,13 +5,34 @@ import copy from '../../js/data/copy.json'
 
 const CardSource = ({ source, language, isLoading, error }) => {
 
+  function renderIconText(type) {
+    switch(type) {
+      case 'Eyewitness Testimony':
+        return 'visibility'
+      case 'Government Data':
+        return 'public'
+      case 'Satellite Imagery':
+        return 'satellite'
+      case 'Second-Hand Testimony':
+        return 'visibility_off'
+      case 'Video':
+        return 'videocam'
+      case 'Photo':
+        return 'photo'
+      default:
+        return 'help'
+    }
+  }
+
   return (
     <div className="card-source">
       {isLoading
           ? <Spinner/>
           : (
             <div className="source-row">
-              <i className="material-icons md-36 source-icon">photo</i>
+              <i className="material-icons source-icon">
+                {renderIconText(source.type)}
+              </i>
               <p>{source.id}</p>
             </div>
           )}