KNOWN BUGS

- open :B does not seem to override keep_blanks 1

- it is not possible to perform XPath searches on namespace nodes
  (it is a limitation of libxml2)

- --skip-xmldecl doesn't work for --file and --pipe (toFile and toFH)
so we need a workaround. The problem here is compression.

- command redirection fails (no output) if the script is passed to
xsh2 as STDIN and encoding is applied (either via $ENCODING variable
or the encoding command). Seems to be due to a (reported) bug in Perl.

