Update POM version for Apache Commons CLI release 1.6.0

Author: garydgregory

pom.xml

@@ -24,7 +24,7 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>commons-cli</groupId>
   <artifactId>commons-cli</artifactId>
-  <version>1.6.0-SNAPSHOT</version>
+  <version>1.6.0</version>
   <name>Apache Commons CLI</name>
 
   <inceptionYear>2002</inceptionYear>