Add some prose about the TI version

Copied and lightly edited from
https://www.cs.cmu.edu/afs/cs/project/ai-repository/ai/lang/scheme/impl/pcscheme/pcs/0.html

www/index.html

@@ -33,8 +33,14 @@
   <h2>Texas Instruments</h2>
   <p>PC-Scheme is a Scheme implementation originally written by
   Texas Instruments. This directory contains the version made
-  public by TI. Note that the public version wasn't as powerful as
-  the commercial version.</p>
+  freely distributable by TI. Note that it wasn't as powerful as
+  the commercial version, which cost $95 and included a reference
+  manual and user guide.</p>
+  <p>PC Scheme includes an optimizing compiler, an emacs-like
+  editor, inspector, debugger, performance testing, foreign
+  function interface, window system and an object-oriented
+  subsystem. Conforms to the Revised^3 Report on Scheme. Also
+  supports the dialect used in Abelson and Sussman's SICP.</p>
   <h2>Ibuki</h2>
   <p>NOTE: Ibuki announced on July 13, 1992, that it has purchased
   the rights to PC Scheme from TI and intends to make it also