Add prose about CWH extensions

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@@ -67,5 +67,18 @@
   under various DOS and OS/2 versions. It even runs on
   Hewlett-Packard's HP95LX. It also runs on Suns with a DOS
   emulator.</p>
+  <h2>Extensions by Carl W. Hoffman</h2>
+  <dl>
+    <dt><code>clcp.tar</code></dt>
+    <dd>Common Lisp Compatibility Package Includes R3RS functions
+    missing from Scheme, macros (DEFMACRO, DOTIMES, DOLIST, DEFUN,
+    SETQ, SETF, PUSH, POP, INCF, DECF, DESCRIBE, ARGLIST), FORMAT,
+    WARN, ERROR, streams and I/O, sequence and list functions</dd>
+    <dt><code>epsilon.tar</code></dt>
+    <dd>Lisp mode for Epsilon, customized for PC Scheme.</dd>
+    <dt><code>r3rs.tar</code></dt>
+    <dd>Adds some of the optional features of R3RS to PC
+    Scheme.</dd>
+  </dl>
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