Version Control With Subversion Source

For issue #79 ("Update 'svnsync sync' and 'svnsync copy-revprops'
syntax and recommendations."):

* en/book/ch09-reference.xml
(svn.ref.svnsync.sw): Note the new --revision (-r) option.
(svn.ref.svnsync.c.copy-revprops, svn.ref.svnsync.c.synchronize):
Document the new syntaxes for these subcommands, adding a
recommendation (by way of warning) to each about specifying the
source URL on the command-line.

Fix unbalanced square brackets. (Karl Fogel weeps in a corner somewhere.)

Finish issue #63 ("New 'svnlook filesize' subcommand").

* en/book/ch09-reference.xml
(svn.ref.svnlook.c.filesize): New section.

Merge from ^/trunk/en r4011, whose log message read like so:

Finish issue #70 ("Basic syntax of WC paths should not be buried in a
chapter named Advanced Topics").

* en/book/ch01-fundamental-concepts.xml
Mention at one of the earliest relevant spots in the text the
at-syntax problem for paths and URLs, with a pointer to the Peg
Revision section.

Reported by: Sam Ruby <sa3ruby>

Finish issue #70 ("Basic syntax of WC paths should not be buried in a
chapter named Advanced Topics").

* en/book/ch01-fundamental-concepts.xml
Mention at one of the earliest relevant spots in the text the
at-syntax problem for paths and URLs, with a pointer to the Peg
Revision section.

Reported by: Sam Ruby <sa3ruby>

* en/stylesheets/custom-html-stylesheet.xsl
Bump custom footer text to refer to version 1.7 instead of 1.6.

Finish issue #22 ("1.7 change: authz section headers are now compared
case-sensitively").

* en/book/ch06-server-configuration.xml
Add a warning about how pre-1.7 Subversion used case-insensitive
comparisons for authz section headers, encourage folks who upgraded
older installations to review their access files.

* branches/1.6/en/book/ch06-server-configuration.xml
Re-add a warning (originally added in r3897 for issue #22) that was
inadvertantly clobbered in r3902.

* en/book/ch07-customizing-svn.xml
Followup to r4006, replacing 'svn diff' output with the 1.7 flavor
instead of 1.6. (Brain's still stuck in "1.6 documentation" mode, I
guess.)

Reported by: danielsh

Finish issue #36 ("Document auto-props escape syntax (;;)").

* en/book/ch07-customizing-svn.xml
(svn.advanced.confarea.opts.config): Document the semicolon escape
trick for autoprops, and show a practical example of them in use.