Update requirements.txt

[lsr00ter]

add pip modules

Description

add docker-py setuptools

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works

[elegantmoose]

Approve:

• adding bounty hunter plugin to list of external plugins

Deny:

• adding bounty hunter to submodules so automatically installed. Core Caldera team doesnt maintain it so will not currently add to list of automatically pulled plugins.
• the install instructions, not everyone uses venv
• conf/default.yml changes, as have no effect

@clenk will need to review the package version pins