Simplify content type shown in dir lists

app/routes/index.js

@@ -2,6 +2,7 @@ import Route from '@ember/routing/route';
 import EmberObject from '@ember/object';
 import { inject as service } from '@ember/service';
 import { isEmpty } from '@ember/utils';
+import simpleContentType from 'inspektor/utils/simple-content-type';
 
 export default Route.extend({
 
@@ -24,10 +25,12 @@ export default Route.extend({
     return this.get('storage.client').getListing(path).then(listing => {
       Object.keys(listing).forEach(name => {
         let item = listing[name];
+        let type = item['Content-Type'] || 'folder';
+        if (type !== 'folder') { type = simpleContentType(type); }
 
         items.push(EmberObject.create({
           name: name,
-          type: item['Content-Type'] || 'folder',
+          type: type,
           size: item['Content-Length'] || null
         }));
       });

app/utils/simple-content-type.js

@@ -0,0 +1,3 @@
+export default function simpleContentType(str) {
+  return str.replace(/;.*$/, '');
+}

tests/unit/utils/simple-content-type-test.js

@@ -0,0 +1,11 @@
+import simpleContentType from 'inspektor/utils/simple-content-type';
+import { module, test } from 'qunit';
+
+module('Unit | Utility | simple content type');
+
+test('it removes the charset portion', function(assert) {
+  let type = 'application/json; charset=UTF-8';
+  let result = simpleContentType(type);
+
+  assert.equal(result, 'application/json');
+});