core: Fix ConfigValues.StorageDomainFalureTimeoutInMinutes name

Renames ConfigValues attribute StorageDomainFalureTimeoutInMinutes to
StorageDomainFailureTimeoutInMinutes.

Change-Id: I246341e8d030aafae6dc5d82998be6c979d9daac
Bug-Url: https://bugzilla.redhat.com/1112036
Signed-off-by: Martin Perina <mperina@redhat.com>