Javadoc
Run a lexer/parser combo, optionally printing tree string or generating
postscript file. Optionally taking input file.
$ java org.antlr.v4.runtime.misc.TestRig GrammarName startRuleName
[-tree]
[-tokens] [-gui] [-ps file.ps]
[-trace]
[-diagnostics]
[-SLL]
[input-filename(s)]