update makefile

tweak api to only import exceptions from datajet.exceptions

Merge pull request #22 from bmritz/19-allow-args-as-a-function-input-…

…to-resolver-functions

19 allow args as a function input to resolver functions

Merge pull request #14 from bmritz/12-bugfix-for-get_dependencies

12 Fix a bug that was preventing successful execution on some data maps that had valid dependency trees.

update version

document requirements on python 3.8 or above