fix many internal links

Fixed a number of internal links that need to
go to the GitHub site.

Ran `make www` to perform the above.

1986/marshall/index.html

@@ -393,7 +393,7 @@ if nothing else.</p>
 <h2 id="alternate-code">Alternate code:</h2>
 <p>Due to the different <a href="compilers.html">conflicting problems</a> with gcc and clang, we
 instead offer the problematic code as an alternate version whereas
-<a href="marshall.c">marshall.c</a> has both the infinite loop and the complicated arg to
+<a href="https://github.com/ioccc-src/temp-test-ioccc/blob/master/1986/marshall/marshall.c">marshall.c</a> has both the infinite loop and the complicated arg to
 <code>_exit()</code> commented out, changing the value passed into <code>_exit()</code> to <code>1</code>.</p>
 <h3 id="alternate-build">Alternate build:</h3>
 <p>To see if your compiler has the problems noted:</p>