Adds new script to do HC to GVCF by chromosome

As one would expect WGS is big, even with the supposed intel speed ups &
lots of cores (which like to crash with concurrent access more often
than not) things are too slow when one tries to HC against an entire WGS
BAM. Thus I've resurrected the idea back from the reduce reads by chr
days and am going to HC by chr and then CombineGVCF after the fact
Tweaks memory requests some more
Die white space, die

Thats german for the white space, the
Adds a by chr GVCF if an interval file is not given

Since things take a long time in WGS, we do GVCF in the HC by chromosome
now if we are not given a specific interval file