workflow: define schemas

[psschwei]

As a user, I want a defined schema to write my beehive workflow in.

This is related with #47 and #48

[psschwei]

Working draft of a workflow

apiVersion: beehive/v1
kind: Workflow
metadata:
  name: beehive-deployment
  labels:
    app: mas-example
spec:
  strategy:
    type: sequence
    output: verbose
  template:
    metadata:
      labels:
        app: mas-example
    agents:
      - name: agent1
      - name: agent2
      - name: agent3
    prompt: Here is where I would put the prompt I would give to my multi-agent workflow