add the concept of a preview date
add a filter that redirects to the preview page for all urls
add a preview page (placeholder)
redirect from the preview page when not in preview

This is to catch people who either bookmark the preview page or get there via a search engine
split the main layout apart into smaller sections so that it can be reused
add a coming soon page
add the concept of a closed conference, and make sure all the redirects happen
Add null checks
review feedback
Remove an old date
Deal with a crash when controllers have duplicate action names
Merge branch 'adrianbanks:add-new-dates' into staging

Add a preview and closed date to the site

Conflicts:
	DDDEastAnglia.Tests/ActionResultExtensions.cs
	DDDEastAnglia.Tests/ConferenceLoaderBuilder.cs
	DDDEastAnglia/App_Start/RouteConfig.cs
	DDDEastAnglia/Domain/Conference.cs
	DDDEastAnglia/Views/Shared/_Layout.cshtml