Change version in package.xml format (#206)

Signed-off-by: Miguel Company <miguelcompany@eprosima.com>

Author: MiguelCompany

package.xml

@@ -1,6 +1,6 @@
 <?xml version="1.0"?>
 <?xml-model href="http://download.ros.org/schema/package_format2.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
-<package format="2">
+<package format="3">
   <name>fastcdr</name>
   <version>2.2.1</version>
   <description>