Add missing licenses (EPL) with an automated script.

Use a script to find which files are missing an EPL header, and to generate & insert an EPL
header in each such file. (Ignore Jython files and auto-generated grammar files.)

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I made the script so that it matched the same formatting as Alex's headers. I also did my best to check that the text generated is consistently correct.

If this isn't what you're looking for, this can at least be a step towards manually adding the licenses.