Change replace_svg_object.py to be per-sample
Change replace_svg_object.py to be per-sample

The script now works on a per-sample basis, this means that it can be
run in parallel for each of the samples that need a figure generated.

EmbrietteH/American-Gut,mortonjt/American-Gut,wasade/American-Gut,biocore/American-Gut,EmbrietteH/American-Gut,wasade/American-Gut,JWDebelius/American-Gut,cuttlefishh/American-Gut,JWDebelius/American-Gut,biocore/American-Gut