Convert complex numbers to real numbers if imaginary part is floating-point 0.0.

This conversion worked only for rational imaginary parts.

src/complex/elem/cl_C_from_R_R_complex1.cc

@@ -17,7 +17,7 @@ const cl_N complex (const cl_R& a, const cl_R& b)
 {
 // Methode:
 // Falls b=0, nur a. sonst komplexe Zahl erzeugen.
-	if (eq(b,0))
+	if (zerop(b))
 		return a;
 	else
 		return allocate_complex(a,b);