Do not emit email events when the state was not changed

This also fixes the trigger regexp to be more in alignment with
the current state machine.

Change-Id: I2da55f4497fd139a0a1ba4f3079a4e97972adb08
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1146433
Signed-off-by: Martin Sivak <msivak@redhat.com>