Update NEWS file

NEWS

+New in 3.1.0:
+
+* Feature: Paperclip now support new migration syntax (sexy migration) that reads better:
+
+      class AddAttachmentToUsers < ActiveRecord::Migration
+        def self.up
+          create_table :users do |t|
+            t.attachment :avatar
+          end
+        end
+      end
+
+  Also, schema-definition level syntax has been added:
+
+      add_attachment :users, :avatar
+      remove_attachment :users, :avatar
+
+* Feature: Migration now support Rails 3.2+ `change` method.
+* API CHANGE: Old `t.has_attached_file` and `drop_attached_file` are now deprecated. You're advised
+  to update your migration file before the next MAJOR version.
+* Bug fix: Tempfile now rewinded before generating fingerprint
+* API CHANGE: Tempfiles are now unlinked after `after_flush_writes`
+
+  If you need to interact with the generated tempfiles, please define an `after_flush_writes` method
+  in your model. You'll be able to access files via `@queue_for_write` instance variable.
+
+* Bug fix: `:s3_protocol` can now be defined as either String or Symbol
+* Bug fix: Tempfiles are now rewinded before get passed into `after_flush_writes`
+* Feature: Added expiring_url method to Fog Storage
+* API CHANGE: Paperclip now tested against AWS::SDK 1.5.2 onward
+* Bug fix: Improved the output of the content_type validator so the actual failure is displayed
+* Feature: Animated formats now identified using ImageMagick.
+* Feature: AttachmentAdapter now support fetching attachment with specific style.
+* Feature: Paperclip default options can now be configured in Rails.configuration.
+* Feature: add Geometry#resize_to to calculate dimensions of new source.
+* Bug fix: Fixed a bug whereby a file type with multiple mime types but no official type would cause
+  the best_content_type to throw an error on trying nil.content_type.
+* Bug fix: Fix problem when the gem cannot be installed on the system that has Asepsis installed.
+
+New in 3.0.4:
+
+* Feature: Adds support for S3 scheme-less URL generation.
+
 New in 3.0.3:
 
 * Bug fix: ThumbnailProcessor now correctly detects and preserve animated GIF.