R-based genetic algorithm.

In some cases the evaluation values of some chromosomes are not agree with
the manually calculated ones while using rbga.bin. During the crossing over
some new chromosomes will be identical with one of their parents and the
evaluation values of their parent will be used in the next generation
avoiding the recalculation. But during mutation these chromosomes can
mutate so the stored evaluation values will not fit the new chromosomes.

Solution:
The evaluation values of the mutated chromosomes should be set to NA.

Corrected script of function is attached. Inserted line is markered by
'####' (line 163.)