Update version for 1.3 beta 1 build

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@268585 13f79535-47bb-0310-9956-ffa450edef68

build.xml

@@ -14,7 +14,7 @@
 
   <property name="Name" value="Ant"/>
   <property name="name" value="ant"/>
-  <property name="version" value="1.3alpha"/>
+  <property name="version" value="1.3beta1"/>
 
   <property name="debug" value="false" />
   <property name="deprecation" value="false" />