patch applied (cabal-branches/cabal-1.6): Validate the docbook xml before processing.

Fri Feb 13 05:41:36 PST 2009 Duncan Coutts * Validate the docbook xml before processing. Apparently xsltproc does not validate against the dtd. This should stop errors creaping back in. M ./Makefile -1 +6 View patch online: http://darcs.haskell.org/cabal-branches/cabal-1.6/_darcs/patches/20090213134...