:param algo_name: make sure it is UPPER

Create and return a dictionary of all our active hash algorithms. Each digester is a 2-tuple ``( digester.update_func(bytes), digest_func(di

Given our bytes and our algorithms, calculate and print our hashes.

Note that contrary to ``git hash-object`` no unix2dos EOL is done!

Prep our bytes.

If there is a file at hashme, read and omnihash that file. Elif hashme is a string, omnihash that.