Merge the following from the English version:

1.140 -> 1.167 handbook/x11/chapter.sgml

Submitted by: Hiroki Kobayashi <solidsneak _at_ hyper.cx>
Review by: Hiroo Ono <hiroo _at_ jp dot FreeBSD dot org>, ryusuke
References: [doc-jp-work 1532, 1539, 1566, 1798, 1799]

Approved by: hrs (mentor)