Document the %APPDATA% shortcut on Windows.
Document the %APPDATA% shortcut on Windows.

* doc/book/book/ch06.xml (svn-ch-6-sect-1.1): Add a footnote explaining
  how "%APPDATA%\Subversion" always points to the user config area.

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