Moved the original files under demo/.
Making it a separate commit to make sure git will know these files have been moved (some heavily modified files would be shown as deleted and added otherwise).
Renamed create_tables.txt to create_tables.sql.
Heavy refactoring.
* Moved most of the functionality from upload.php and readlog.php into a newly created LogBook class and made the demo app use that class instead.
* Converted direct MySQL calls to object-oriented PDO calls (PHP's mysql extension is being deprecated).
* Made the code work with PHP 5.4.
* Improved (well, I hope) file parsing, freq-to-band conversion and other stuff.

What's left for this stage is to move any database-related functionality from search.php into the LogBook class and make the former use the latter.