ItemTransport clas --> transport.items module

Conflicts:
	django/website/chn_spreadsheet/tests.py
	django/website/hid/tests/views_tests.py
	django/website/hid/views.py

Replace with ItemTransport object, which needs to be instantiated. I
think it can be reused between calls to its methods so there's no need
to create new ones all over the place, but that's what I have done so
far. I'm a bit uncertain about module level variables, and not
everything is contained in a class.

These are no longer used by transport, and nobody else should be using
them.

Actualy they are now also a class.
The existing functions still exist and call into the class
(wastefully creating an instance every time but I expect these
to go away and rewrite the clients to use an instance of the
transport class directly.

By default the router derives the url names from
the model name (which it gets from the queryset)
which is Message

Note: transport still uses the explicit views

tests broken

This also fixes error handling for malformed dates

Conflicts:
	django/website/chn_spreadsheet/tests.py

Conflicts:
	django/website/data_layer/handlers.py
	django/website/data_layer/tests/handler_tests.py
	django/website/settings.py
	django/website/transport/data_layer_transport.py

Conflicts:
	django/website/hid/views.py