兼容java doc中文字符

Author: yinanwu

build.gradle

@@ -29,6 +29,10 @@ apply plugin: 'elasticsearch.esplugin'
 apply plugin: 'maven'
 apply plugin: 'license'
 
+compileJava.options.encoding = 'UTF-8'
+compileTestJava.options.encoding = 'UTF-8'
+javadoc.options.encoding = 'UTF-8'
+
 ext.projectSubstitutions = [:]
 // license of this project
 licenseFile = rootProject.file('LICENSE.txt')