build: Prettify `make publish' output

Print each file to be packed into the tarball individually on a separate
line, not all in one shot.
build: Preserve permissions on source files

This sets the correct permissions to the source files, not the generated
output. Of course, the generated files retain the permissions of the
original source.
build: Minify CSS files

Uses the YUI compressor to minify css files.
build: Minify HTML files

Uses the htmlcompressor to minify generated HTML files.
404: Use absolute paths to resources

A 404 error can be served from anywhere, so using relative paths is
impossible. Consider:

   chriscummins.cc/not-a-file.html

vs:

   chriscummins.cc/not/a/path/file.html
uni: Add dissertation and sustainability submissions
build: Separate local from remote content control

The one-shot publishing was awful. Server-side file control has been
abstracted into a new file `Makefile.publishing', and `Makefile.private'
has been burnt and destroyed (good riddance).
build: Add support for PHP files
index: Move from static html to PHP

This allows a visitor cookie to change the welcome message from "Hi." to
"Hello again." for repeat visitors.
assets: Use Google CDN for JQuery

Don't host a local copy.