SHOGUN: Accurate, scalable metagenomic quantification with shallow shotgun sequencing

Adding some extra functionality with the fixing of issues #14, #15.

1. We can summarize KEGG tables into pathways
2. We can now summarize a KEGG table into modules and pathways given a KEGG table
3. You can now specify the taxacut parameter as a float on the command line (.5 <= taxacut < 1.0)
4. Contaminate filtering was sped up through BURST any mode