ZOOKEEPER-2378 upgrade ivy to recent version (phunt)

git-svn-id: https://svn.apache.org/repos/asf/zookeeper/trunk@1733505 13f79535-47bb-0310-9956-ffa450edef68

build.xml

@@ -111,7 +111,7 @@ xmlns:cs="antlib:com.puppycrawl.tools.checkstyle.ant">
     <property name="contrib.dir" value="${src.dir}/contrib"/>
     <property name="recipes.dir" value="${src.dir}/recipes"/>
 
-    <property name="ivy.version" value="2.2.0"/>
+    <property name="ivy.version" value="2.4.0"/>
     <property name="ivy.url"
               value="http://repo2.maven.org/maven2/org/apache/ivy/ivy" />
     <property name="ivy.home" value="${user.home}/.ant" />