This also fixes error handling for malformed dates

Conflicts:
	django/website/hid/views.py

It is now possible to specify a date format string (as used by
strptime) for date columns in the spreadsheet.

Conflicts:
	django/website/chn_spreadsheet/tests.py

https://trello.com/c/81jGz7rm/35-apply-minimal-dashboard-design

Resolved conflicts:
	django/website/hid/tables.py

https://trello.com/c/dEa42JFS/21-bug-column-display-of-time-to-be-dd-mmm-yyyy

Was getting:

~/workspace/internewshid/django/website➔ ./manage.py --version
/home/marks/workspace/internewshid/django/website/data_layer/models.py:11: RemovedInDjango19Warning: Model class data_layer.models.Message doesn't declare an explicit app_label and either isn't in an application in INSTALLED_APPS or else was imported before its application was loaded. This will no longer be supported in Django 1.9.
  class Message(DataLayerModel):

/home/marks/workspace/internewshid/django/website/data_layer/models.py:11: RemovedInDjango19Warning: Model class data_layer.models.Message doesn't declare an explicit app_label and either isn't in an application in INSTALLED_APPS or else was imported before its application was loaded. This will no longer be supported in Django 1.9.
  class Message(DataLayerModel):

1.8.2

'transport' app imports 'data_layer' so changed their order in
LOCAL_APPS

Conflicts:
	django/website/hid/views.py
	django/website/media/css/styles.css
	django/website/templates/base.html
	django/website/templates/registration/login.html

Still need to handle row numbers correctly