precision on email_filter

The filtering regexp should not allow greedy matchers (such as .*) but
use non greedy ones (such as .*?).  One want to escape dots as well.

Additionally, whenever one want to add several emails, he should use a
YAML list.

Change-Id: I9deea0893151358ddde9b1ec5a40c322c45d7ff2
Reviewed-on: https://review.openstack.org/18350
Reviewed-by: James E. Blair <corvus@inaugust.com>
Approved: James E. Blair <corvus@inaugust.com>
Tested-by: Jenkins
1 file changed