Use newer version of Ivy in example

Contributed-by: Gintautas Grigelionis
Pull request: #90

Author: jaikiran

asciidoc/install.adoc

@@ -54,7 +54,7 @@ If you want to use Ivy only in your Ant build scripts, and have an internet conn
 [source,xml]
 ----
 <project xmlns:ivy="antlib:org.apache.ivy.ant">
-    <property name="ivy.install.version" value="2.1.0-rc2"/>
+    <property name="ivy.install.version" value="2.5.0"/>
     <condition property="ivy.home" value="${env.IVY_HOME}">
       <isset property="env.IVY_HOME"/>
     </condition>

asciidoc/samples/build.xml

@@ -38,7 +38,7 @@
 
     <!-- here is the version of Ivy we will use. change this property to try a newer
          version if you want -->
-    <property name="ivy.install.version" value="2.4.0"/>
+    <property name="ivy.install.version" value="2.5.0"/>
     <property name="ivy.jar.dir" value="${basedir}/ivy"/>
     <property name="ivy.jar.file" value="${ivy.jar.dir}/ivy.jar"/>
 

src/example/go-ivy/build.xml

@@ -38,7 +38,7 @@
 
     <!-- here is the version of ivy we will use. change this property to try a newer
          version if you want -->
-    <property name="ivy.install.version" value="2.0.0-beta1"/>
+    <property name="ivy.install.version" value="2.5.0"/>
     <property name="ivy.jar.dir" value="${basedir}/ivy"/>
     <property name="ivy.jar.file" value="${ivy.jar.dir}/ivy.jar"/>