Added initial code to run otu_category_significance.py on a per-body-site basis. No HTML new output has been added yet, just the raw output files are being created.
Refactored code to use QIIME workflow framework and made code closer to meeting pycogent coding guidelines.
Disabled otu category significance output by default (for now at least) until we decide whether we want this feature or not.
Fixed a bug introduced during refactor.
Merge pull request #21 from jrrideout/issue_3

otu_category_significance.py and significant refactor