random number generator syntax warning  

```
Warning: Using 'twister' to set RAND's internal state causes RAND, RANDI, and RANDN to use legacy
random number generators.  This syntax is not recommended.  See Replace Discouraged Syntaxes of rand
and randn to use RNG to replace the old syntax. 
> In dispatcher (line 121)
In runrats (line 97) 
```