[FEAT] - Create mapping for Elasticsearch index during crawl

[wambozi]

Is your feature request related to a problem? Please describe.
Currently, if an index specified in an Elasticsearch crawl doesn't exist, no mapping is applied to it when the crawl is initiated. The index is created using dynamic mapping in Elastic when the first document is indexed.

Describe the solution you'd like
A POST like:

curl -XPOST http://localhost:8081/crawl -d
{
  "index": "starwars-english",
  "url": "https://starwars.fandom.com",
  "type": "elasticsearch",
  "mapping": {
    "settings": {
      "analysis": {
        "filter": {
          "autocomplete_filter": {
            "type": "edge_ngram",
            "min_gram": 1,
            "max_gram": 20
          }
        },
        "analyzer": {
          "autocomplete": {
            "type": "custom",
            "tokenizer": "standard",
            "filter": [
              "lowercase",
              "autocomplete_filter"
            ]
          }
        }
      }
    },
    "mappings": {
      "properties": {
        "uri": {
          "type": "keyword"
        },
        "meta": {
          "properties": {
            "ogimage": {
              "type": "text"
            },
            "title": {
              "type": "text",
              "analyzer": "autocomplete",
              "search_analyzer": "standard"
            },
            "description": {
              "type": "text",
              "analyzer": "autocomplete",
              "search_analyzer": "standard"
            },
            "keywords": {
              "type": "text",
              "analyzer": "autocomplete",
              "search_analyzer": "standard"
            }
          }
        },
        "source": {
          "properties": {
            "h1": {
              "type": "text",
              "analyzer": "autocomplete",
              "search_analyzer": "standard"
            },
            "h2": {
              "type": "text",
              "analyzer": "autocomplete",
              "search_analyzer": "standard"
            },
            "h3": {
              "type": "text",
              "analyzer": "autocomplete",
              "search_analyzer": "standard"
            },
            "h4": {
              "type": "text",
              "analyzer": "autocomplete",
              "search_analyzer": "standard"
            },
            "p": {
              "type": "text",
              "analyzer": "autocomplete",
              "search_analyzer": "standard"
            }
          }
        }
      }
    }
  }
}

Will detect if the index in the request exists. If not, it will create the index with the mapping provided.