[redland-dev] Removing support for expat in Raptor 2.0.7+ - requiring libxml2

[Dave Beckett]

Expat hasn't had a release in 4+ years and I can simplify the Raptor code
and configuration if libxml2 is required; it has been the default and
recommended parser for over 5 years.   libxml2 is a very widely installed
library and as far as I'm concerned, is the definitive XML library for C.  I
won't be removing the SAX2 abstraction since that's working fine.

I guess there's a small possibility somebody might want a smaller XML
subsystem to be usable but it can't be based on an unmaintained library.
There are things like lxml (python + C), Xerces-C++ (C++), etc. but
integrating them would be tricky.  I'm not doing this work.

... and if you were wondering, yes libxml did inspire the librdf name

Cheers

Dave