Permit the setting of Build Schedule Delay to "0".

Delay not needed with Replication Events. Also fixed dependent projects
feature to no longer rely on this default 3 seconds delay. [FIXED JENKINS-22812]

Change-Id: Ic11f0fb7b9e43e95ae7dec71c30fe1e6fab1e8ac
Merge pull request #143 from scoheb/permit-no-delay

Permit the setting of Build Schedule Delay to "0". Delay not needed with Replication Events