whoops, fixed invalid seq check for trim_graph
whoops, fixed invalid seq check for trim_graph

jas14/khmer,souravsingh/khmer,Winterflower/khmer,Winterflower/khmer,jas14/khmer,jas14/khmer,ged-lab/khmer,souravsingh/khmer,F1000Research/khmer,Winterflower/khmer,kdmurray91/khmer,F1000Research/khmer,souravsingh/khmer,kdmurray91/khmer,kdmurray91/khmer,F1000Research/khmer,ged-lab/khmer,ged-lab/khmer