remove iWorkbenchPartSite parameter from CompositeFactory.createComposite interface

Most implementations use this to get a Display, which can be also be got directly from parent.
Only ActionBtnComposite used the site for getService, which can also be got from a
WorkbenchWindow, obtained with PlatformUI.getWorkbench().getActiveWorkbenchWindow()

Conflicts:

	uk.ac.gda.dls.client/src/uk/ac/gda/dls/client/views/BatonStatusCompositeFactory.java
	uk.ac.gda.dls.client/src/uk/ac/gda/dls/client/views/MetadataObjectCompositeFactory.java
	uk.ac.gda.dls.client/src/uk/ac/gda/dls/client/views/ScannableCompositeFactory.java