Add 'working with ImageJ API' section to jython scripting tutorial on wiki

This post continues discussions started on github ( around updating the instructions for interacting with the ImageJ API on the Jython scripting wiki pages.
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In my experience, the biggest barrier scientists have when trying to extend or automate an image analysis pipelines is doing something that is not already covered in a tutorial or forum/stackoverflow question. How do you find what you need to import? how do you use it? What is a constructor?

If you haven’t worked with Java, then interacting with Java classes and even finding the documentation for them is not obvious or straightforward and most question answers or examples will explain that you have to from ij import IJ at the top of the script without providing a link to the javadocs for the ij package and showing which other classes and packages you can import or how to use them.

I think this problem can be addressed by providing a few straightforward examples demonstrating how someone would attack a problem by searching for classes in the ImageJ javadocs and then using them in a basic script. @LThomas started a new section in the Jython Scripting wiki and I will add a few examples to try and address this.

Please feel free to contribute, fix my mistakes, or suggest anything.