Overduin, Sam authored Nov 27, 2019 and Overduin, Sam committed Nov 27, 2019

- Added TaxaTree (like 1.23.456.7890) parser from reads & store in index

barcode_index.hpp:
- Added data structure in BarcodeIndex to store TaxaTree mapping
  to taxids (taxatree_codes_).
- Added data structure in EdgeEntry to store taxid_distribution_.
- Added attribute to EdgeEntry for taxonomy_.

barcode_info_extractor.hpp:
- Added method to get taxids for a EdgeID