release: Update package.xml version to 2.1.1

Author: jcarpent

package.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <package format="3">
   <name>hpp-fcl</name>
-  <version>2.1.0</version>
+  <version>2.1.1</version>
   <description>An extension of the Flexible Collision Library.</description>
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