Add sources and javadoc to the standaloneJar artifact (#91)

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Author: oleg-nenashev

build.gradle

@@ -152,6 +152,9 @@ publishing {
 
             project.shadow.component(publication)
 
+            artifact sourcesJar
+            artifact javadocJar
+
             pom {
 
                 name = "${baseArtifact}-standalone"