[PATCH] allow svnsync to translate non-UTF-8 log messages to UTF-8 (v. 2)

Attached are the new patch and log message.

I have already shared one test repository with this mailing list that
is useful in testing that revprops are re-encoded properly. Since
then, I have created two more: test2 is useful in testing that
directory properties (in this case `svn:ignore`) are re-encoded, and
test3 is useful in testing that line endings are normalized to
Unix-style in revprops (and that the "# normalized" message is still
there). Archives of these new repositories have also been attached.
Also, this shell script makes testing with these repositories *much*
easier: http://pastebin.com/gz1pmngc

#! /usr/bin/env sh
TEST=test3 # change this line to test with a different repository
rm -Rf ${TEST}_mirror
svnadmin create ${TEST}_mirror
cat <<'EOF' > ${TEST}_mirror/hooks/pre-revprop-change
#! /usr/bin/env sh
USER="$3"

if [ "$USER" = "svnsync" ]; then exit 0; fi

echo "Only the svnsync user can change revprops" >&2
exit 1
EOF
chmod +x ${TEST}_mirror/hooks/pre-revprop-change
svnsync init \
--username svnsync --source-encoding ISO-8859-1 \
file://`pwd`/${TEST}_mirror file://`pwd`/${TEST}
svnsync sync \
--username svnsync --source-encoding ISO-8859-1 \
file://`pwd`/${TEST}_mirror