Cleaner output of top-level tests.

[mostlyobvious]

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  /Users/pawel/Code/rails_event_store/rails_event_store/spec/request_metadata_spec.rb:5: warning: already initialized constant RailsEventStore::DummyEvent
  /Users/pawel/Code/rails_event_store/rails_event_store/spec/middleware_integration_spec.rb:8: warning: previous definition of DummyEvent was here
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  RailsEventStoreActiveRecord::EventRepository
    initialize with adapter
    provide own event implementation
    behaves like event_repository
      what you get is what you gave
      reads all stream events forward & backward
      has or has not domain event
      reads batch of events from all streams forward & backward
      data attributes are retrieved
      does not have deleted streams
      metadata attributes are retrieved
      knows last event in stream
      created event is stored in given stream
      just created is empty
      reads batch of events from stream forward & backward

  RailsEventStoreActiveRecord::MigrationGenerator
        create  b.migrate.20160809222222_create_event_store_events.rb
    should match /ActiveRecord::Migration$/
        create  b.migrate.20160809222222_create_event_store_events.rb
    should match /ActiveRecord::Migration\[4\.2\]$/

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