Version Control With Subversion Source

* trunk/src/de/book/ch07-customizing-svn.xml
- Fixes ticket #237 (cf. http://www.svnbook.de/report/6).

* trunk/src/de/book/ch07-customizing-svn.xml
- Fixes ticket #236 (cf. http://www.svnbook.de/report/6).

* src/zh/po/svnbook.po:
Sync with source files, no translation change.

* trunk/src/de/book/ch07-customizing-svn.xml
- Fixes ticket #235 (cf. http://www.svnbook.de/report/6).

* src/zh/po/svnbook.po:
2104 translated messages, 1200 fuzzy translations, 334 untranslated messages.

* www/index.zh.html
Format adjust.

* src/tools/po4a/lib/Locale/Po4a/Xml.pm:
Update to 2009-04-05, do not include commented out entities.

* src/tools/fo-stylesheet.xsl:
Set hyphenate.verbatim=0, remove superfluous hyphens.

* src/en/book/ch03-advanced-topics.xml
Add id="" to variable list containing the svn:externals URL magic syntax.

Patch by: Neels J Hofmeyr <neels{_AT_}elego.de>

* src/en/book/ch05-repository-admin.xml
(fsfs-reshard.py):
Remove repetition "used used".
(Packing FSFS filesystems):
Keep only "filesystem" in "operating system filesystem",
also avoid one repeated use of word "penalty".

Patch by: Neels J Hofmeyr <neels{_AT_}elego.de>

Follow-up r3476, ISO XML entity tricks for translation, simply is better

Thanks, Nicolas François <nicolas DOT francois AT centraliens DOT net> !

Update Chinese translation(2068 tr, 1236 fu, 334 un)

ISO XML entity tricks for translation

Because svnbook source xml use external entity instead of xinclude,
so after xinclude process, the external entity will be expanded. currently,
po4a can't treat those strings as equivalent, therefore we must translate
every source xml separately.