Update Document Creation Process

- Add proper Build and Makefile files in Source/Doc directory
- Switch preprocessing from pp to m4 which is more supportable across platforms
- Building of documentation is still done manually as needed, but it is now easy to do under either Windows or Linux using provided files

Source/Doc/Clean.cmd

@@ -0,0 +1,10 @@
+@echo off
+setlocal
+
+if exist *.gfm del *.gfm
+if exist *.txt del *.txt
+if exist *.dw del *.dw
+if exist *.html del *.html
+if exist *.tex del *.tex
+if exist *.pdf del *.pdf
+if exist *.tmp del *.tmp