Add rec-flag for BeamBackgroundWordFiller

This MR addresses a problem that I found with threading-tests, though it has nothing to do with multi-threading.

The BeamBackgroundWordFiller relies on the RawInfoSummaryForTag object (for number-of-spacepoints and such). When turning the trigger off (required these days to run with MT), the RawInfoSummaryForTagWriter gets turned off but the BeamBackgroundWordFiller is still scheduled, leading to dangling data-dependency.

This MR introduces a flag to turn BeamBackgroundWordFiller on/off (surprisingly, this didn't exit) that gets turned off when any of the ingredients isn't there. In practice, that means the BeamBackgroundWordFiller can run only if at least the system reconstruction of all subdetectors (+Trigger) runs.

Note that this is all about RecExCommon and the old configuration.