opencast scheduling: does not check schedule on Galicaster start

[andiempett]

Opencast schedule is only checked on the long heartbeat after the short heartbeat has successfully connected to opencast. So creating a mediapackage and starting the recording can have a delay of the long heartbeat.
i propose a change so that on Galicaster startup the opencast schedule is retrieved and recordings can start immediately, similar to behaviour pre-2.0.x

[smarquard]

We would also like this change.