title: incompatible gradle dependencies
body: <p>I'm seeing an error message in the build.gradle file for an android library in my app. The dependencies block is shown below:</p>
  
  <pre><code>dependencies {
      implementation fileTree(dir: 'libs', include: ['*.jar'])
      implementation 'com.android.support:appcompat-v7:27.0.2'
      testImplementation 'junit:junit:4.12'
      androidTestImplementation 'com.android.support.test:runner:1.0.1'
      androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'
      compile 'de.hdodenhof:circleimageview:2.2.0'
      compile 'com.android.support:recyclerview-v7:27.0.2'
      compile 'com.beloo.widget:ChipsLayoutManager:0.3.7@aar'
  }
  </code></pre>
  
  <p>The message I'm seeing is:</p>
  
  <pre><code>all com.android.support libraries must use the exact same version specification
  </code></pre>
  
  <p>Apparently, both version 27.0.2 and 21.0.3</p>
  
  <pre><code>Found versions 27.0.2, 21.0.3. Examples include com.android.support:animated-vector-drawable:27.0.2 and com.android.support:support-v4:21.0.3 less... (⌘F1)
  </code></pre>