Changed execution behaviour for brics derived from SyncedInputBric
Changed execution behaviour for brics derived from SyncedInputBric

Brics with sync input now process input as soon as any input is available,
avoiding deadlocks possible with the previous behaviour.

databricxx/databricxx,aguetlein/databricxx,databricxx/databricxx,oschulz/databricxx,oschulz/databricxx,aguetlein/databricxx