add href support to mdMenuItem vuematerial#463

Author: marcosmoura

docs/src/pages/components/Menu.vue

@@ -158,7 +158,7 @@
               <md-button md-menu-trigger>Bottom Right</md-button>
 
               <md-menu-content>
-                <md-menu-item>My Item 1</md-menu-item>
+                <md-menu-item href="http://google.com">My Item 1</md-menu-item>
                 <md-menu-item>My Item 2</md-menu-item>
                 <md-menu-item>My Item 3</md-menu-item>
               </md-menu-content>

src/components/mdMenu/mdMenuItem.vue

@@ -1,8 +1,10 @@
 <template>
   <md-list-item
     class="md-menu-item"
-    :class="classes"
     @click.native="close"
+    :class="classes"
+    :href="href"
+    :target="target"
     :disabled="disabled">
     <slot></slot>
   </md-list-item>
@@ -14,6 +16,8 @@
 
   export default {
     props: {
+      href: String,
+      target: String,
       disabled: Boolean
     },
     data: () => ({