title: Error:Cause: buildToolsVersion is not specified in build.grade (Project:xxx)
body: <p>Right now I am trying to integrate Fabric with Crashlytics (<a href="https://docs.fabric.io/android/fabric/integration.html" rel="nofollow">https://docs.fabric.io/android/fabric/integration.html</a>) into an existing android application.  </p>
  
  <p>Following the integration instructions provided by Fabric I add <code>apply plugin: 'com.android.application'</code> to the root directory of my "build.grade (Project.NumenuApp)" file. I click to Sync Gradle, it fails, and I receive this error <code>Error:Cause: buildToolsVersion is not specified.</code> Android studio states that my plugins should be declared at the Module not Project level.</p>
  
  <p>I already have the buildTools set in the "build.grade (Module:app)" file. My question is why is this happening and what can I do to remedy it?  I have posted my code below.  Thanks in advance. - Adrian</p>
  
  <p>build.grade (Project:NumenuApp)</p>
  
  <pre><code>// Top-level build file where you can add configuration options common to all     sub-projects/modules.
  
  buildscript {
      repositories {
          jcenter()
          maven { url 'https://maven.fabric.io/public' }
      }
      dependencies {
          classpath 'com.android.tools.build:gradle:1.5.0'
          // NOTE: Do not place your application dependencies here; they belong
          // in the individual module build.gradle files
          classpath 'io.fabric.tools:gradle:1.+'
      }
  }
  apply plugin: 'com.android.application'
  apply plugin: 'io.fabric'
  
  allprojects {
      repositories {
          jcenter()
          maven { url 'https://maven.fabric.io/public' }
      }
  }
  
  task clean(type: Delete) {
      delete rootProject.buildDir
  }
  </code></pre>
  
  <p>build.grade (Module:app)</p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 23
      buildToolsVersion "23.0.2"
  
  defaultConfig {
      applicationId "com.numenu.numenuapp"
      minSdkVersion 21
      targetSdkVersion 23
      versionCode 1
      versionName "1.0"
  }
  buildTypes {
      release {
          minifyEnabled false
          proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
      }
  }
  }
  
  dependencies {
      compile fileTree(dir: 'libs', include: ['*.jar'])
      testCompile 'junit:junit:4.12'
      compile 'com.android.support:appcompat-v7:23.1.1'
      compile 'com.android.support:design:23.1.1'
      compile 'com.android.support:support-v4:23.1.1'
      compile 'com.android.support:recyclerview-v7:23.1.1'
  }
  </code></pre>