FUNCTION: LieTools/DimRLA
USAGE: Dimg(Gt); Dimg(Gtype,rnk);
SYNOPSIS: Dimg(Gt) yields the dimension of a reductive
  Lie Algebra Gt. If its argument is a pair of the form 
  Gtype,rnk, then it yield the dimension of
  simple Lie algebra of that Cartan type.
  We also allow for abelian factors, e.g.
       Dimg(A1*T1*T1) = Dimg(A1*T2) = 5
  (the `T2` here is to indicate the 2-dimensional abelian
  Lie algebra.)
EXAMPLE: 
> LieTools[Dimg](E6);
                                  78

> LieTools[Dimg](E,6);

                                  78

SEE ALSO: LieTools[Rnk], LieTools[DimSLA]
