To render this documentation to PDF or HTML, use one of:

1)  dblatex *.xml
2)  xmlto --with-fop pdf *.xml
3)  publican build --langs=en-US --formats=pdf

This is now encoded in the build now as well, publican is
used by default if it is installed, but BOOK_TOOLCHAIN is
available to force an alternative (configure environment
variable, e.g. "BOOK_TOOLCHAIN=xmlto ./configure ...").