GlobalFunctions code coverage

* smwfGetSparqlDatabase someone has to write a proper factory method
for this and until that day @codeCoverageIgnore
* smwfGetLinker
* smwfNumberFormat can't be sufficiently tested therefore @codeCoverageIgnore

Change-Id: Ia7b1cb00b6eac862fb4ab8f9e71eeb4455991b3d