Refactor: move functions accessing species CODES to species.py
Merge pull request #952 from RickMohr/refactor-CODES-functions

Refactor: move functions accessing species CODES to species.py
Modify delete template tag to match audit logic

There was a bug on staging because these two different code paths treat UDFs differently. This problem is fixed by using the same test in the template tag that is used in the audit system.
Update delete button activation condition

Reads the correct permissions for tree when tree is the object to be deleted.
Fix import of species_codes_for_regions