OPENNLP-1351: Add ONNX model support for doccat and namefinder

[jzonthemtn]

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[jzonthemtn]

There are some checkstyle issues I will be fixing.

[kinow]

Looking great @jzonthemtn ! Added a few comments, feel free to ignore the ones about stream/newlines/etc. There's one issue in a pom.xml, with a duplicated entry for opennlp-tools. But after fixing that, and ignoring checkstyle with mvn clean test -Dcheckstyle.skip the build passes OK.

👍 🎉

[kinow]

Leaving one comment on the XML that I think the IDE changed. But other than that, it looks like a good start, then we can refine later if needed 👏

Thanks Jeff!

[jzonthemtn]

@kinow I missed that pom file! I fixed it in the last push and added a few more unit tests.