[xml] Using xmlDict for newDoc

[Jason Viers <lists beanalby net>]

I've noticed that when parsing a doc the xmlDict is part of the 
xmlParserCtxt, and when xmlNewDoc() is used there's no dictionary.  Is 
there any reason I wouldn't want to manually give a dict to the new doc 
and use it when constructing nodes? 

It seems to work with preliminary tests, but I'm not yet experienced 
enough with libxml to tell whether using a xmlDict without an 
xmlParserCtxt is bad voodoo.

Thanks
Jason