Changing Doxyfile so that doxygen will scan files matching the

pattern *.dox.

Also adding files src/README.dox indicating how to add documentation
to the "main page", and src/mpi/README.dox as an example of adding
a page of supplementary information.

Don't know if there is a "standard" way of doing this, but it seems
to work, and saves us having to stuff too much detail into real
source files.

This commit was SVN r964.

Doxyfile

@@ -372,7 +372,7 @@ INPUT                  =
 # *.c *.cc *.cxx *.cpp *.c++ *.java *.ii *.ixx *.ipp *.i++ *.inl *.h *.hh *.hxx *.hpp 
 # *.h++ *.idl *.odl *.cs *.php *.php3 *.inc
 
-FILE_PATTERNS          = *.c *.h *.cc
+FILE_PATTERNS          = *.c *.h *.cc *.dox
 
 # The RECURSIVE tag can be used to turn specify whether or not subdirectories 
 # should be searched for input files as well. Possible values are YES and NO. 

src/README.dox

@@ -0,0 +1,23 @@
+/** @mainpage
+
+@section mainpage_introduction Introduction
+
+This is the introduction.
+This is the introduction.
+This is the introduction.
+This is the introduction.
+This is the introduction.
+This is the introduction.
+This is the introduction.
+
+@section main_install Installation
+ 
+This is the installation section.
+This is the installation section.
+This is the installation section.
+This is the installation section.
+This is the installation section.
+This is the installation section.
+This is the installation section.
+
+*/

src/mpi/README.dox

@@ -0,0 +1,15 @@
+/**
+
+@page page_mpi The src/mpi directory
+
+@section page_mpi_introduction Introduction
+
+This is the introduction.
+This is the introduction.
+This is the introduction.
+This is the introduction.
+This is the introduction.
+This is the introduction.
+This is the introduction.
+
+*/