* doc/book/book/ch06.xml: Removed duplicated word.
* doc/book/book/ch06.xml: Removed duplicated word.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion