Bump version number

Author: btalb

package.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <package format="2">
   <name>benchbot_robot_controller</name>
-  <version>2.1.1</version>
+  <version>2.2.1</version>
   <description>The benchbot_robot_controller package</description>
 
   <maintainer email="b.talbot@qut.edu.au">Ben Talbot</maintainer>