PhotoManager: Use settings for photo cycle time.
Tidy: Rename project_defines to data.
Readme: Add a list of dependencies.
Photo DB: Add a big reminder!
Value Model: Add some return value checking.
Weather: Use GeoIP for position; add error checks.

Switch from using a web-based service for the IP address-based location
searching to a locally stored database. Also added extra checking for
(hopefully) 99% of what can go wrong.
Tidy: Stop committing bloody temporary files!
Thrd: Add a bug reminder.
Weather: Update the weather periodically.
Photo DB: Random selection of photo more sane.

Selecting a random photo based on rating now takes into account the
number of photos at a rating. This is to prevent a single photo with a
rating=100 dominating other photos with rating=50.
Pages, Value, Weather: Show city name with weather
Weather: Catch IOError when no network getting IP.
Value: Create _value attribute earlier.

This is to prevent an exception that (somehow!) occurs when update is
called before sel._value = None is executed in the constructor.