create version of tooling that does not depend on gradle to run

[pahjbo]

As most of the business logic is done with XSLT it is perfectly possible to make an executable that can run these scripts without having to set up a gradle build environment. This would make the tooling look less "Java"y, which would hopefully remove a barrier to adoption.

[pahjbo]

perhaps even python https://pypi.org/project/saxonche/ but unfortunately https://pypi.org/project/pyschematron/ does not allow xslt functions, so not so easy...

[pahjbo]

The slight impediment to doing this is that some of the plugin is currently using some built-in gradle functionality to do things - e.g. the inheritance, dependencies and jar unpacking - it would be a shame to have to reproduce all of this functionality "outside" gradle .