Restored qatest 1

This test was skipped in July, because it was too slow. However with the improvements to the event based hazard calculator the test is now fast (2+ hours -> 1 minute) and it can be restored. Notice a few things:

1. the event_loss_table is not tested, it will be done in a separate pull request (see https://bugs.launchpad.net/oq-engine/+bug/1225288)

2. the numbers are different than before because the hazard calculator has changed

3. I have changed the assertAlmostEqual facility of LossCurve with a special case when asset_value is 0.0

4. now the test save the actual values in a directory called 'actual': that makes it easy to compare the numbers when something change and the tests break.

The tests are green: http://ci.openquake.org/job/zdevel_oq-engine/296