feat(list): added no-borders attribute for lists

if you apply the no-borders attribute it will remove all borders inside
of a list. Added a test case for showing this.

ionic/components/list/modes/ios.scss

@@ -87,3 +87,12 @@ $list-ios-header-color:               #333 !default;
 .list[inset] + .list[inset] {
   margin-top: 0;
 }
+
+&.hairlines .list[no-borders],
+.list[no-borders] {
+  ion-header:after,
+  .item:before,
+  .item:after {
+    border-width: 0;
+  }
+}

ionic/components/list/modes/md.scss

@@ -66,3 +66,11 @@ $list-md-header-color:           #858585 !default;
 .list[inset] + .list[inset] {
   margin-top: 0;
 }
+
+.list[no-borders] {
+  ion-header:after,
+  .item:before,
+  .item:after {
+    border-width: 0;
+  }
+}

ionic/components/list/test/no-borders/index.ts

@@ -0,0 +1,7 @@
+import {App} from 'ionic/ionic';
+
+
+@App({
+  templateUrl: 'main.html'
+})
+class E2EApp {}

ionic/components/list/test/no-borders/main.html

@@ -0,0 +1,30 @@
+<ion-toolbar><ion-title>List No Borders</ion-title></ion-toolbar>
+
+<ion-content class="outer-content">
+  <ion-list no-borders>
+    <ion-header>
+      List Header
+    </ion-header>
+
+    <ion-switch>
+      <icon wifi item-left></icon>
+      Wifi
+    </ion-switch>
+
+    <ion-item>
+      <icon heart item-left></icon>
+      Affection
+      <ion-note item-right>
+        Very Little
+      </ion-note>
+    </ion-item>
+
+    <ion-item>
+      <icon home item-left></icon>
+      Home
+      <ion-note item-right>
+        Where the heart is
+      </ion-note>
+    </ion-item>
+  </ion-list>
+</ion-content>