Version Control With Subversion Source

Tweak the book buildsystem so that it is actually designed to be reusable.

* tools/Makefile.base: Send most of the content of this file to the two new
files added in this commit.
* tools/Makefile.base-vars, tools/Makefile.base-rules: New. Tweaked to add the
capability to build books which don't have any image files.

Makefile refactoring.

* tools/Makefile.base:
Strip redundant 'BOOK_' prefix from the name of make variables.
(NAME, OUTNAME, STYLESHEET): New variables.

* nb/Makefile, ru/Makefile: Adjust to changed name of FO_XSLTPROC_OPTS.

* zh/book/ch05.xml: contributed by nannan

* zh/book/ch05.xml: contributed by nannan

* zh/book/ch05.xml: change file encode!

YACT (yet another Chinese translator).

* tools/Makefile.base (+install-book-html, +install-book-html-chunk):
Add missing $(BOOK_INSTALL_DIR) dependency.
* tools/bin/find-xsl.py: Set missing svn:eol-style=native property.

* en/README: Fix inconsistent FOP version number in example commands.

* en/README: Capitalize the 'B' in 'DocBook'.

* zh/book/ch04.xml: Contributed by nannan and me