Add JavaDoc task for jitpack

Author: koji-1009

jasper/build.gradle

@@ -22,3 +22,28 @@ dependencies {
     androidTestImplementation 'com.android.support.test:runner:1.0.2'
     androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
 }
+
+task sourcesJar(type: Jar) {
+    classifier = 'sources'
+    from android.sourceSets.main.java.sourceFiles
+}
+
+task javadoc(type: Javadoc) {
+    source = android.sourceSets.main.java.sourceFiles
+    classpath += project.files(android.getBootClasspath().join(File.pathSeparator))
+}
+
+task javadocJar(type: Jar, dependsOn: javadoc) {
+    classifier = 'javadoc'
+    from javadoc.destinationDir
+}
+
+task classesJar(type: Jar) {
+    from "$buildDir/intermediates/classes/release"
+}
+
+artifacts {
+    archives classesJar
+    archives javadocJar
+    archives sourcesJar
+}