docs/162154: [handbook] section 6.4.2 misordering.

[Manolis Kiagias]

Here is a complete patch, also with version information removed:

http://www.freebsdgr.org/all/en_US.ISO8859-1/books/handbook/x11/x11.patch

And a test build here:

http://www.freebsdgr.org/all/en_US.ISO8859-1/books/handbook/x-config.html

This clears up the chapter a bit, I doubt we need to reference 7.3 and 
earlier versions specifically anymore. Any objections?