label the processString with _gen for generator specific relvals

- only relevant for submission to computing; not relevant for performance / IB 
- label the processString with _gen for generator specific relvals
- as requested by @anorkus to ease bookeping and relmon-ification of generator relvals

Hello @bendavid @inugent , this will address the relmon report needs you expressed last week.
Will back port this chance to 7_1 too, in anticipation of when we'll have GEN relvals there too.