ouput validation in tests

[wdpypere]

It would be very nice to be able to do extra validation on generated files in the tests. For instance if you are generating an XML file with metaconfig that you can actually get the output and run it through an XML parser to see if it's valid.
Something for example like:

use Test::More;
use Test::Quattor::TextRender::Metaconfig;
use XML::Parser;

my $u = Test::Quattor::TextRender::Metaconfig->new(
        service => 'some-service',
        )->test();

my $p = XML::Parser->new(Style => 'Tree');
my $t;
eval { $t = $p->parse($u->output); };
ok(! @$, "No XML parsing errors");

done_testing;