Version Control With Subversion Source

* src/en/book/ch03-advanced-topics.xml
* src/en/book/ch09-reference.xml
* src/en/book/ch06-server-configuration.xml
* src/en/book/ch04-branching-and-merging.xml
* src/en/book/ch02-basic-usage.xml
* src/en/book/ch07-customizing-svn.xml
Various fixes found while porting copyedit changes to ORA's tree.
This also includes a revert of the partial change to close up spaces
between footnote markers and preceding text, not because that change
was wrong, but because it was a tip-of-the-iceburg approach.
Consistency is easier to automate around.