Update Jacoco Gradle Plugin to 0.8.0 (#85)

Author: vanniktech

build.gradle

@@ -7,7 +7,7 @@ buildscript {
     dependencies {
         classpath 'com.gradle.publish:plugin-publish-plugin:0.9.1'
         classpath 'com.github.ben-manes:gradle-versions-plugin:0.13.0'
-        classpath 'com.vanniktech:gradle-android-junit-jacoco-plugin:0.7.0'
+        classpath 'com.vanniktech:gradle-android-junit-jacoco-plugin:0.8.0'
     }
 }