declared and installed DefiningIdealOfUnitaryGroupOfHead
declared and installed DefiningIdealOfUnitaryGroupOfSemiSimpleFactor

using the previously installed DefiningIdealOfUnitaryGroupOfHead
x * ( x * S ) -> ( x * S ) * x

just for cosmetical reasons
GeneralElement is now an attribute for IsHomalgModule
GeneralElementsOfFiltration now sets the component RingOfGeneralElement

in CertainObject( filt, degrees[i] )
DefiningIdealOfUnitaryGroupOfHead now uses then new feature of GeneralElementsOfFiltration

and returns the defining ideal over the smaller ring

R := CertainObject( filt, 0 )!.RingOfGeneralElement