title: Android dependency 'io.reactivex.rxjava2:rxandroid' has different version
body: <p>When sync project with gradle files, Android Studio shows this error:</p>
  
  <pre><code>Android dependency 'io.reactivex.rxjava2:rxandroid' has different version for the compile (2.0.1) and runtime (2.1.0) classpath. You should manually set the same version via DependencyResolution
  </code></pre>
  
  <p>I have try to solve it with:</p>
  
  <pre><code>resolutionStrategy.force 'io.reactivex.rxjava2:rxandroid:2.1.0'
  </code></pre>
  
  <p>But with the same result.</p>
  
  <p>This problem occurs when I change 'compile' with 'implementation' in the libraries definition</p>
  
  <p>This is how I define the rest of the rx libraries:</p>
  
  <pre><code>buildscript {
  
      ext.retrofitVersion = '2.4.0'
      ext.rxVersion = '2.2.1'
      ext.rxAndroidVersion = '2.1.0'
      ext.okhttpVersion = '3.8.1'
      ext.rxKotlinVersion = '2.0.0'
  
      ...
  
  
      repositories {
          mavenCentral()
          jcenter()
      }
  
  }
  //Rx &amp; Retrofit 2 **********************************
  implementation("com.squareup.retrofit2:retrofit:$retrofitVersion") {
      // exclude Retrofit’s OkHttp peer-dependency module and define your own module import
      exclude module: 'okhttp'
  }
  implementation "com.squareup.retrofit2:converter-gson:$retrofitVersion"
  implementation "com.squareup.retrofit2:adapter-rxjava2:$retrofitVersion"
  implementation "io.reactivex.rxjava2:rxkotlin:$rxKotlinVersion"
  implementation "com.squareup.okhttp3:okhttp:$okhttpVersion"
  implementation "com.squareup.okhttp3:logging-interceptor:$okhttpVersion"
  implementation "io.reactivex.rxjava2:rxandroid:${rxAndroidVersion}"
  implementation "io.reactivex.rxjava2:rxjava:$rxVersion"
  </code></pre>
  
  <p>Any ideas how can I solve this problem?</p>