Add release target: BlueJ about teals-minecraft

[mdonoughe]

I gave this a try because my school has only BlueJ installed and the school laptops are locked down to the extent the teacher doesn't think we'd be able to use anything else.

I'm not that good with BlueJ, and maybe there are ways around this, but I think all the code not in tealsmc.mods needs to be moved to a jar file. I originally tried just loading the src directory, and BlueJ went into a loop of opening more and more new windows to the same package and I had to terminate the process to make it stop.

All the JAR files should be in the same directory (or combined?) because BlueJ wants the user to add all the required libraries in the BlueJ preferences dialog (not as part of the project?). Maybe some of these can be avoided by using dynamic loading for libraries the student isn't expected to compile against (Gradle).

After moving some code into a JAR file I had trouble with paths in GradleStart being incorrect. It looks like the working directory is expected to be different than what BlueJ uses.

I got to the part where Minecraft initializes, but the latest version of BlueJ uses its own built-in JDK 11, and the old version of Forge+Minecraft used by this project seem to require JDK 8 or older. I get a NoSuchMethodException when Forge is trying to make a field writable. Eclipse gave a different error, but also failed to start when using JDK 11.

This seems like too much for IT and students to handle, especially given the switch to remote learning for the remainder of the school year, so I'm not going to pursue it further. Maybe this information will help somebody.