index alias & ingest pipeline generation

[yoosful]

Hello, I'd like to suggest introducing two new features to this library.
My colleagues and I are willing to contribute if the proposal looks okay.

1. index alias generation

POST _aliases
{
"actions": [
  {
    "add": {
      "index": "logs-nginx.access-prod",
      "alias": "logs"
    }
  }
]
}

2. ingest pipeline generation

PUT _ingest/pipeline/my-pipeline
{
"description": "My optional pipeline description",
"processors": [
  {
    "set": {
      "description": "My optional processor description",
      "field": "my-long-field",
      "value": 10
    }
  },
  {
    "set": {
      "description": "Set 'my-boolean-field' to true",
      "field": "my-boolean-field",
      "value": true
    }
  },
  {
    "lowercase": {
      "field": "my-keyword-field"
    }
  }
]
}

[kmiura-1002]

Hi!
Aelias thinks it is unnecessary to use this tool to manage this.
The purpose of this tool is to do version control with respect to the definition of the index.
Aliases may be part of the index definition, but we think it is more appropriate to manage them in Elasticsearch's ILM or curator.

The same applies to pipelines, which we do not think are necessary at this time.
However, we are aware that this is something we should consider adding at a later time.

Thank you.