v0.1.3

Changelog

a39a7a4 chore: add creep CLI test workflow step
a58e164 chore: bump go mod version -> v1.14
21c65cd chore: create go CI workflow
7c576da fix: check status code before determining mime type in download
76f3f8b fix: exit func prints err to STDERR
6ce9749 fix: print usage to STDOUT, return 0 status code
ecee9e3 refactor: rename internal dir to pkg
31ff718 refactor: rename primary download function