Bug 43853

client-side rng validation (as used by bxe) currently fails in proxied
environments, because the include hrefs are not correctly resolved.
we have a strange re-implementation of a fallback resolver in
src/webapp/lenya/xslt/resources/translate-rng-includes.xsl that just knows
contexts, not proxies. it really needs to go away rsn.
for now, i'm removing the context prefix and apply a proxy transform later on
(which means the proxy transformer has to be re-configured to include
rng:includes...)

we should really be more careful with using cocoon-internal protocols in files
that will potentially be parsed on clients (currently, these are rngs and xslt -
mozEdit anyone?). imnsho, they should not be served from files at all but via
the module sitemaps, with proper proxy transforms applied.