title: cardslib error resource android:attr/foregroundInsidePadding is private while targeting SDK 26
body: <p>Okay, I have created a completely new project in Android Studio 3.0. Gradle build works fine in this newly instantiated project, until I insert the following lines in my module's <code>build.gradle</code></p>
  
  <pre><code>dependencies {
      ...
      compile 'com.github.gabrielemariotti.cards:cardslib-core:2.1.0'
      compile 'com.github.gabrielemariotti.cards:cardslib-cards:2.1.0'
      compile 'com.github.gabrielemariotti.cards:cardslib-recyclerview:2.1.0'
  }
  </code></pre>
  
  <p>Here is the error I get in the Build log</p>
  
  <pre><code>/home/sparker0i/.gradle/caches/transforms-1/files-1.1/appcompat-v7-26.0.1.aar/e06e09188fb79d4d895b39247477d1c1/res/values/values.xml
  Error:(246, 5) resource android:attr/foregroundInsidePadding is private
  </code></pre>
  
  <p>When I double click on it, I get a <code>values.xml</code> file (merged one), where the pointer is at</p>
  
  <pre><code>&lt;dimen name="abc_action_bar_content_inset_material"&gt;16dp&lt;/dimen&gt;
  </code></pre>
  
  <p>My minimum SDK version is 16, target SDK is 26. I am using Android Studio 3.0 Beta 2, build tools version is 26.0.1. Gradle plugin 3.0.0-beta2.</p>
  
  <p>I bet this is because of a slightly outdated Cardslib library. Is there no way to fix this? (Removing those lines from dependencies works fine)</p>