Add 127.0.0.1 to default localhost addresses

@_localhosts is now localhost and 127.0.0.1
Tests initially failed due to some testing recording with 127.0.0.1
Tests were fixed by explicitly specifying Replay.allow "127.0.0.1"
Used Replay.allow in before and Replay.localhost in after for each test that uses "127.0.0.1" to avoid fragility in the future - it actually works to just specify .allow once, but that's deceptive as re-ordering and deleting of tests could randomly cause tests to fail
Tests now pass