Added javadoc task

Author: jitpack-io

library/build.gradle

@@ -28,8 +28,22 @@ task sourcesJar(type: Jar) {
     from android.sourceSets.main.java.srcDirs
     classifier = 'sources'
 }
+
+task javadoc(type: Javadoc) {
+    failOnError  false
+    source = android.sourceSets.main.java.sourceFiles
+    classpath += project.files(android.getBootClasspath().join(File.pathSeparator))
+}
+
+// build a jar with javadoc
+task javadocJar(type: Jar, dependsOn: javadoc) {
+    classifier = 'javadoc'
+    from javadoc.destinationDir
+}
+
 artifacts {
     archives sourcesJar
+    archives javadocJar
 }
 
 // uncomment to build a jar file in addition to the default aar file