updating cli to use command cli library

[jamiehewitt15]

Fixes #42

Changes proposed in this PR:

• updating cli to use command cli library
• Before you would get an error message if calling the help command before setting the envs. I've changed this so that you can always call the help command, either npm run cli h or npm run cli help
• We now support flexible argument ordering with the introduction of flags (more details in the updated readme)
• Everything is backwards compatible, you can still write the commands in the previous format and they will still work

[paulo-ocean]

lgtm