Need to normalize salt-api responses

Salt-api is very useful, but also in need of response normalization. This issue is partially tracked through a few different issues, and it would be helpful to keep progress in a single place. See: #20301 #18510 jenkinsci/saltstack-plugin#18 jenkinsci/saltstack-plugin#36

Here are some short examples demonstrating the problems:

Most state responses include a result key which contains the appropriate success status. So far so good

[{
  "outputter": "highstate",
  "data": {"pws-3.dev.mpl.ru":   {
    "file_|-/some/file":     {
      "comment": "No directory to create /some/file in",
      "name": "/other/file",
      "start_time": "16:21:10.068787",
      "result": false,
      "duration": "0.947 ms",
      "__run_num__": 6,
      "changes": {}
    }
  }}
}]

Other times the API does not include the necessary info at all:
CLI

# salt 'web1' cmd.run 'false 1'
web1:
ERROR: Minions returned with non-zero exit code

API

{
    "return": [
        {
            "web1": ""
        }
    ]
}

This same issue occurs with the service execution module. Here is an example of a service failing to restart:

{
    "info": [
        {
            "Arguments": [
                "klsdklsd"
            ],
            "Function": "service.restart",
            "Minions": [
                "web1"
            ],
            "Result": {
                "web1": {
                    "return": false
                }
            },
            "StartTime": "2016, May 27 14:08:28.970138",
            "Target": "web1",
            "Target-type": "glob",
            "User": "jenkins",
            "jid": "20160527140828970138"
        }
    ],
    "return": [
        {
            "web1": false
        }
    ]
}

And some errors are in different structures

[{
  "outputter": "highstate",
  "data": {"minion-name": ["Rendering SLS 'base:hostname' failed: mapping values are not allowed here; line 40..."]}
}]

Or

[{"infra01": "ERROR executing 'pillar.get': The following keyword arguments are not valid: output=raw"}]

The problem isn't just errors either. Commands like the manage.present runner respond with successful, but again completely different output, making parsing difficult.

[["minion1","minion2","salt"]]

Overall, the responses generated by salt-api are somewhat all over the board making for constant edge cases increasing complexity.

Start with the response examples in this issue and review linked issues #20301, #18510, jenkinsci/saltstack-plugin#18, and jenkinsci/saltstack-plugin#36 to identify overlapping requirements. Trace the salt-api paths for highstate, cmd.run, service.restart, errors, and manage.present, then define and test a consistent response contract covering success, failure, and error cases.