Version Control With Subversion Source

* trunk/src/de/book/ch07-customizing-svn.xml
- Fixes ticket #230 (cf. http://www.svnbook.de/report/6).

Convert svn:externals to 1.5 relative URL format.

Make the descriptions of FSFS shards a little more first-class.

* src/en/book/ch05-repository-admin.xml
(Revision files and shards): New sidebar, gutted from the text
around fsfs-reshard.py, and amended to also include a mention of
the new packed format.
(fsfs-reshard.py): Refer to new sidebar now when talking about
revision files and shards.
(Packing FSFS filesystems): Refer to new sidebar.

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

Fix a typo.

Found by: Malte Helmert <helmert{_AT_}informatik.uni-freiburg.de>

Fix Makefile target 'epub'

* src/en/book/ch05-repository-admin.xml
Add sections for 'FSFS Configuration' and 'Packing FSFS filesystems'.

Patch by: hwright
(Tweaked, heavily, by me.)

* src/ru/book/app-quickstart.xml : Changes from el_ <el_@...>.

* trunk/src/de/book/ch05-repository-admin.xml
- Fixes ticket #229 (cf. http://www.svnbook.de/report/6).

* trunk/src/de/book/ch05-repository-admin.xml
- Fixes ticket #228 (cf. http://www.svnbook.de/report/6).

* trunk/src/de/book/ch05-repository-admin.xml
- Fixes ticket #227 (cf. http://www.svnbook.de/report/6).