Remove rgblib.

I have never used it and it's probably been broken for years.

doc/index.htm

@@ -12,7 +12,6 @@
 	<li><a href="geninfo.htm">ASMotor General Information</a>
 	<li><a href="asm.htm">xASM Documentation</a>
 	<li><a href="link.htm">xLink Documentation</a>
-	<li><a href="lib.htm">xLib Documentation</a>
 	<li><a href="fix.htm">RGBFix Documentation</a>
 	<li><a href="rgb0.htm">The RGB0-2 ObjectFileFormat</a>
 </ul>