Function transform 

pub fn transform(
    xml: &str,
    xslt_files: &[(&str, &str)],
) -> Result<String, Error>

Transform XML using a set of XSLT files.

The first entry in xslt_files is the main stylesheet (entry point); the rest are written alongside it so that xsl:import href="foo.xslt" resolves relative to the same directory.

Returns the transformed output as a string.

Errors

Returns Error::Xslt if Saxon is not found, fails to run, or produces non-zero exit status.