Adding ruleworks grammar. (#4097)

* Added comment to ruleworks.g4 file.

* Fixng grammar to add EOF to fix test failures.

* Altered action to action_ to avoid conflict on some targets

ruleworks/README.md

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+This is the grammar for RuleWorks, which was intended as a follow on to OPS5. 
+OPS5 was originally developed at Carnegie Melon University and then adopted
+by Digital Equipment Corporation (DEC). The source code contains copyrights from 
+DEC.
+
+The late 1980's into the early 1990's were the age of expert systems. Digital 
+Equipment rewrote OPS5 in Bliss (it was originally written in Lisp) and then 
+wrote an expert system name XCON (for Expert Configurator.) If you ever saw a 
+copy of the VMS hardware sales book you know why such an expert system was needed.
+
+
+*****************************************************************************
+*  MODIFIED BY:
+ *	DEC	Digital Equipment Corporation
+ *	CPQ	Compaq Computer Corporation
+ *
+ *  MODIFICATION HISTORY:
+ *
+ *	22-Dec-1992	DEC	Initial version.
+ *	.
+ *	.
+ *	.
+ *	01-Dec-1999	CPQ	Releasew ith GPL
+****************************************************************************
+
+The software was obtained from VMS Software, Inc (VSI) freeware site.
+
+https://vmssoftware.com/community/freeware/
+
+Below is the opening paragraph from the freeware_readme.txt file included with
+the software.
+
+***************************************************************************
+RuleWorks is a language, compiler (with debugger), and Run-Time Library for
+constructing high performance, modular, object-oriented, forward-chaining,
+rules-based applications.  (RuleWorks is an evolutionary step past OPS5.)
+It provides portability by producing ANSI C sources which can then be 
+compiled with any of the leading C or C++ compilers. There is a Run-Time 
+Library for each supported platform and C compiler.
+**************************************************************************
+
+ And the following is lifted from one of the source code files:
+
+**************************************************************************
+RuleWorks - Rules based application development tool.
+
+Copyright (C) 1999  Compaq Computer Corporation
+
+This program is free software; you can redistribute it and/or modify it 
+under the terms of the GNU General Public License as published by the 
+Free Software Foundation; either version 2 of the License, or any later 
+version. 
+
+This program is distributed in the hope that it will be useful, but 
+WITHOUT ANY WARRANTY; without even the implied warranty of 
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 
+Public License for more details. 
+
+You should have received a copy of the GNU General Public License along 
+with this program; if not, write to the Free Software Foundation, 
+Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+Email: info@ruleworks.co.uk
+**************************************************************************
+
+The email bounces back with "the domain ruleworks.co.uk couldn't be found."
+
+Not too surprising given that the source code files are 25 years old.
+
+The examples directory contains 3 sample programs. The one of interest (advent) is
+an incomplete port of the Adventure program that made the rounds in the early 
+1980's. All 3 programs parse cleanly.

ruleworks/desc.xml

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+<?xml version="1.0" encoding="UTF-8" ?>
+<desc xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../_scripts/desc.xsd">
+   <antlr-version>^4.10</antlr-version>
+   <targets>Antlr4ng;CSharp;Cpp;Dart;Go;Java;JavaScript;PHP;Python3;TypeScript</targets>
+   <inputs>examples</inputs>
+</desc>