Add Mbs slit entrance device

[oliwenmandiamond]

Mbs analyser has extra information recorded for the device to do with the analyser slits e.g

		completedRegion.setAnalyserSlitDirection(entranceSlitInformationProvider != null? entranceSlitInformationProvider.getDirection(): "vertical");
		completedRegion.setAnalyserSlitSetting(entranceSlitInformationProvider != null? (int) entranceSlitInformationProvider.getRawValue(): 0);
		completedRegion.setAnalyserSlitShape(entranceSlitInformationProvider != null? entranceSlitInformationProvider.getShape(): "unknown");
		completedRegion.setAnalyserSlitSize(entranceSlitInformationProvider != null? entranceSlitInformationProvider.getSizeInMM(): 0.0);

This should be implemented as it's own device and then passed to the analyser and then combine its configuration with this one (done by adding it as a child device).