MFbed: Update the German documentation set.

doc/de_DE.ISO8859-1/books/fdp-primer/book.sgml fixes only
doc/de_DE.ISO8859-1/books/fdp-primer/doc-build/chapter.sgml new translation [X]
doc/de_DE.ISO8859-1/books/fdp-primer/stylesheets/chapter.sgml new translation [X]
doc/de_DE.ISO8859-1/books/handbook/disks/chapter.sgml 1.271 -> 1.273
doc/de_DE.ISO8859-1/books/handbook/kernelconfig/chapter.sgml 1.169 -> 1.171
doc/de_DE.ISO8859-1/books/handbook/mirrors/chapter.sgml 1.428 -> 1.429
doc/de_DE.ISO8859-1/books/handbook/ppp-and-slip/chapter.sgml 1.175 -> 1.176

Obtained from: The FreeBSD German Documentation Project.

• Translated by jkois@