Update to rails 4.0.0
Monkey patch PostgreSQLAdapter to make enums work
Remove multiline regular expression anchors from validations
Replace attr_accessible with strong parameters
Eliminate deprecated scope and association arguments
Replace deprecated `scoped` method with `all`
Rails now defaults to using PATCH for updates
IntegrationTest is now in ActionDispatch not ActionController
Replace deprecated finder methods
RoutingError is now UrlGenerationError
Remove format specifier from RSS feed route tests
Remove deprecated assert_blank and assert_present from tests
Detect test environment correctly
Set hostname for signed requests correctly
Always allow %{attribute} in model validation error messages
Fix rails 4 compatibility issues in migrations
Avoid singleton serialisation errors
Precompile various vendor assets
Allow iD and Potlatch 2 to load assets outside the asset pipeline
Ignore exceptions clearing sessions

Rails 3 sessions can't be loaded by rails 4 but reset_session also
fails because it tries to clear the session, which tries to load it
in to clear it.

So monkey patch the session to ignore exceptions during clear so
that out normal reset-on-exception logic will reset the session.