Create Rails::Subscriber::TestHelper and use it to make ActiveRecord subscriber tests run in both sync and async scenarios.

This reverts commit 8665c754.

reduce max size of fixture IDs to fix sqlite2 tests, because sqlite2 was getting negative and changing values for ID field. See http://www.sqlite.org/datatypes.htmlSigned-off-by: NYehuda Katz <wycats@gmail.com>

Get everyone running on Rails.env and fix the broken environment settings for script/console and script/dbconsole

Send the connection in AR notifications to avoid checking out new connections in threads just for logging purposes.

API Change: Returning a "X-Cascade: pass" header triggers the cascade
instead of a 404 response.

Signed-off-by: NJosé Valim <jose.valim@gmail.com>

[#3671 state:committed]
Signed-off-by: NJeremy Kemper <jeremy@bitsweat.net>