checkpoint add initial inc/md2html.cfg file

Adjust HTML phase names and filenames under inc.

Improve phase documentation in inc/README.md.

Added inc/md2html.cfg as an initial markdown to HTML configuration
file.  The inc/md2html.cfg file is undergoing design evaluation and
thus may change.  Nevertheless the comments in inc/md2html.cfg give
some hints as to how HTML files will be formed from markdown files.

inc/footer.default.html

@@ -0,0 +1,10 @@
+<!-- START: this line start content from: /inc/footer.default.html -->
+
+<div class="footer">
+  <hr>
+  <h2>Footer</h2>
+  <p>This is where stuff at the bottom of all pages would be found.</p>
+  <a href="#top">Jump to top</a>
+</div>
+
+<!-- END: this line ends content from: /inc/footer.default.html -->