Append buildType name to appName if not release

modify_app_name.gradle

applicationVariants.all { variant ->
    variant.mergeResources.doLast {
        def buildTypeName = variant.buildType.name
        if (!buildTypeName.equals("release")) {
            println "Modifying app name"

            File valuesFile = file(
                    "${buildDir}/intermediates/res/${variant.dirName}/values/values.xml")
            String content = valuesFile.getText('UTF-8')

            def root = new XmlSlurper().parseText(content)
            def appNameNode = root.depthFirst().
                    find { it.name() == 'string' && it.@name == 'app_name' }
            if (appNameNode != null) {
                def oldName = appNameNode.text()
                def newName = oldName + " " + buildTypeName
                println "Modifying app name from " + oldName + " to " + newName
                appNameNode.replaceBody newName
            }
            // Write modified node and all the file to disk
            valuesFile.write(groovy.xml.XmlUtil.serialize(root), 'UTF-8')
        }
    }
}