Refactor & Polish

[arm4b]

• [x] Use Native Vagrantfile features env, args for shell provisioning
• [x] Make sure ~/.st2 CLI auth creds are set for both vagrant and root
• [x] Better automated message in Slack when everything was set up
• [x] Sort/Remove unneeded core Action Aliases
• [x] Include !ship it command
• [x] ...
• [x] Better approach to verify if HUBOT_SLACK_TOKEN was set #8

[LindsayHill]

Nice tidy-up work here @armab Wonder if we should make some similar changes to https://github.com/StackStorm/st2-ansible-vagrant?

[arm4b]

@LindsayHill Will do!