Converted a logEntry call to use the magic "now" keyword.
Initial commit of existing session checks in session_login endpoint.
Initial commit of session_logout endpoint.
Made token the primary key in the sessions database table.
Added field to address a piece of data to another person.
Modified structure of main_data DB table.

Changed which fields are compulsory, and added capability for more data
to be stored.
Added abstraction code to create DB transactions.
Initial commit of translation functionality.

Includes a bunch of en_AU translation strings.
Moved point at which config.php is loaded to allow for translations.
Converted a lot of strings to use the translation functionality.