add TomsFastMath

doc/copyright.texi

@@ -153,6 +153,22 @@ to the following restrictions:
 @end verbatim
 @copynext
 
+@heading TomsFastMath
+
+Tom's fast math (bignum support)
+
+@verbatim
+
+TomsFastMath is public domain.
+
+Note some ideas were borrowed from LibTomMath and OpenSSL.  All of the code is original or ported
+from LibTomMath [no code was ported from OpenSSL].  As such the origins and status of this code
+are both public domain.
+
+@end verbatim 
+
+@copynext
+
 @heading Michael J. Fromberger
 
 The RSA/DH support for libhcrypto.