Whitespace cleanups.

MFen:
1.376 -> 1.379 advanced-networking/chapter.sgml
1.142 -> 1.143 basics/chapter.sgml
1.59 -> 1.63 boot/chapter.sgml
1.216 -> 1.222 cutting-edge/chapter.sgml
1.247 -> 1.248 disks/chapter.sgml
1.51 -> 1.66 firewalls/chapter.sgml
1.330 -> 1.331 install/chapter.sgml
1.110 -> 1.111 introduction/chapter.sgml
1.161 -> 1.163 kernelconfig/chapter.sgml
1.111 -> 1.115 l10n/chapter.sgml
1.132 -> 1.133 mail/chapter.sgml
1.274 -> 1.288 security/chapter.sgml

Obtained from: The FreeBSD Russian Documentation Project