Fix up doc publishing as part of release.

Author: John Engelman

gradle/ghPages.gradle

@@ -1,8 +1,14 @@
 apply plugin: 'org.ajoberstar.git-publish'
 
+if (project.hasProperty('githubToken')) {
+  System.setProperty('org.ajoberstar.grgit.auth.username', project.githubToken)
+}
+
 gitPublish {
     repoUri = 'https://github.com/johnrengelman/shadow.git'
 
+    branch = 'gh-pages'
+
     contents {
         from 'build/asciidoc/html5'
         into('api') {
@@ -12,4 +18,4 @@ gitPublish {
 }
 
 tasks.gitPublishPush.dependsOn asciidoctor
-tasks.gitPublishPush.dependsOn groovydoc
+tasks.gitPublishPush.dependsOn groovydoc

gradle/publish.gradle

@@ -150,5 +150,5 @@ publishPlugins { task ->
 }
 
 task release() {
-    dependsOn 'assemble', 'bintrayUpload', 'publishPlugins', 'publishGhPages'
+    dependsOn 'assemble', 'bintrayUpload', 'publishPlugins', 'gitPublishPush'
 }