add a test to verify that single k-mers will be 'assembled' if paths in both direction are branching
add a test to verify that single k-mers will be 'assembled' if paths in both direction are branching

souravsingh/khmer,ged-lab/khmer,souravsingh/khmer,ged-lab/khmer,souravsingh/khmer,ged-lab/khmer