CE-3269: Implement batch deployment logic

The batch deployment and undeployment have been introduced. This merge request also includes the DB modification.

In the case of batch deployment an AWX job executes multiple deployments, so the relationship between the awx_job and ioc_deployment tables has been modified to allow multiple ioc_deployment entries to be associated with a single awx_job.

The batch deployment request towards AWX looks like (In the case if we want to deploy IOC1 to host1 and IOC2 to host2):

{
  "limit": "host1:host2",
  "extra_vars": {
    "iocs_to_undeploy_json": [],
    "iocs_to_deploy_json": [
      {
        "name": "IOC1",
        "git": "https://gitlab.esss.lu.se/group/ioc1-repo.git",
        "version": "tag1",
        "description": "Test IOC 1"
      },
	  {
        "name": "IOC2",
        "git": "https://gitlab.esss.lu.se/group/ioc2-repo.git",
        "version": "tag2",
        "description": "Test IOC 2"
      },
    ]
  }
}

Closes CE-3269, CE-3268