Feature Request: output xml like --covarage-xml in phpunit does

[dstockto]

It would be very useful to be able to use phpcov to output the files and directory structure that are created when phpunit is run with the --coverage-xml. For instance, phpdox uses that structure to enrich its output but it cannot enrich with multiple directories which is necessary if a project consists of multiple phpunit runs and then merging of the various bits of output into their individual reports.