Synchornize with English revisions + typo fixes.
handbook/boot/chapter.sgml: typo fixes
handbook/config/chapter.sgml: 1.223 -> 1.225
handbook/desktop/chapter.sgml: 1.66 -> 1.67
handbook/install/chapter.sgml: 1.337 -> 1.338
handbook/mirrors/chapter.sgml: 1.420 -> 1.421
handbook/x11/chapter.sgml: 1.177 -> 1.178
porters-handbook/book.sgml: 1.769 -> 1.772
Obtained from: The FreeBSD Simplified Chinese Project