test for tickets 259 and 469; fix adding R+Rhelp

also added test for tickets 469 and 259

various fixes were provided by Gerhard Pfister
(https://github.com/Singular/Sources/commit/9434d56e8ef4f81efbcce8576989b9e7dba52103#diff-d01266b9465d2911c15a58b7bcf28fa1R6514
https://github.com/Singular/Sources/commit/0c42a847c2651462997b32adb623b79f38d133f5
)

still failing:
```
LIB("normal.lib");
ring rng = 0, (T(1),T(2),T(3),y,x ),(dp(3),dp(2) );
ideal I = x^9+y*x^5-y^5+y^3,T(3)*x^2-y^3+y,T(3)*y^2-x^7-y*x^3,T(2)*y-x^4,T(2)*x^3-T(3)*y+x^3,T(1)-T(3)*x,T(3)^2+T(2)*x-y*x^5-y^2*x+x,T(2)*T(3)-y^2*x^2+x^2,T(2)^2+T(2)-T(3)*x;
I = std(I);
dim(I);
def J =  equidim(std(I))[1];
J;
genus(J,"pri");  // = 6, wrong!
genus(J);  // =9
genus(J,"nor"); // = 9

```