add support for 'null' values in json objects

examples/app.js

@@ -15,10 +15,11 @@ new Vue({
                   b: 'a',
                   a: 'hello word',
                   asd2: 1,
-                  asd: false
+                  asd: false,
+                  foo: null
                 }
               }
         }
     },
     components: {JsonViewer}
-})
+})

json-box.vue

@@ -11,6 +11,7 @@
 <script>
 import JIcon from './json-icon'
 import JsonString from './types/json-string';
+import JsonNull from './types/json-null';
 import JsonNumber from './types/json-number';
 import JsonBoolean from './types/json-boolean';
 import JsonObject from './types/json-object';
@@ -34,7 +35,9 @@ export default {
     },
     computed: {
         valueType() {
-            if (Array.isArray(this.value)) {
+            if (this.value === null) {
+                return 'Null';
+            } else if (Array.isArray(this.value)) {
                 return 'Array';
             } else if (typeof this.value === 'object') {
                 return 'Object';

types/json-null.vue

@@ -0,0 +1,18 @@
+<template>
+    <span class="json-null">null</span>
+</template>
+
+<script>
+export default {
+    name: 'JsonNull',
+    props: {
+        jsonValue: Object
+    }
+};
+</script>
+
+<style lang="scss">
+.json-null {
+    color: #e08331;
+}
+</style>