Create `agent` Object, add `agent` and `owner` to `endpoint`

[jonrau-at-queryai]

Related Issue:

#986

Description of changes:

• Adds owner to device, endpoint, and network_endpoint.
• Adds a new agent object that defines various sensors and agent.
• Adds the new agent object to device, resource, and endpoint.
• Adds is_applied Boolean to policy.

[pagbabian-splunk]

Please check the description of name : "Organization name for the Autonomous System."

[mikeradka]

@jonrau-at-queryai Looks good to me, just approved, but there is a small merge conflict with the CHANGELOG. Could you update that so we can merge?

[jonrau-at-queryai]

@jonrau-at-queryai Looks good to me, just approved, but there is a small merge conflict with the CHANGELOG. Could you update that so we can merge?

Looks like it's fixed, but it bumped all of the approvals again.

[Aniak5]

Looks great! Thanks for this addition, its super useful!