Clarification BORE in EUDAQ2

[arummler]

Doing the conversion from eudaq1 to eudaq2 I stumbled in the manual about the new role of the BORE. In chapter 6 it says: "The first Event object has a flag BORE by the method eudaq::Event::SetBORE()" but it is not said that it has to be done explicitly. The Ex0Producer listed just before does not tag a BORE. The second mention is in the glossar: "BORE beginning-of-run-event, basically a run header." In the system producers it is not done consistently: both AIDA as well as EUDET TLU producers tag a BORE; the NI producer does not. Coming from eudaq1 that poses a few questions which should be clarified in the manual:

• BORE has to be set explicitly by SetBORE(); example should be given (included in example producer)
• Different from eudaq1 is not a special event which does not contain data but only the run header; the first "normal" event just can get this property.
• Is it optional of mandatory to set. If it is optional what is the benefit? In the example data collector "Ex0TgTsDataCollector.cc" it seems to be mandatory as it checks for presence of all BOREs.