Do not download DTD
|Reported by:||strk||Owned by:||strk|
Prevent DTD downloading while producing the documentation. This is similar to #963 but for general use, not only for Hudson.
Since r9327 we have the support in place to look for offline mathml2.dtd and could expand on it. This ticket is to forbid network access (—nonet switch to xsltproc) and provide all it takes to make it possible (a configure switch to explicitly name the place where you can find the DTDs, for example).