title: Adding ngram to existing index
body: <p>Is there a way to add ngram matching to existing index? I saw plenty examples in documentation how to create index which will search through using ngrams, but when I try to follow those instructions I get error:</p>
  
  <pre><code>{"error":"IndexAlreadyExistsException[[nameOfIndex] already exists]","status":400}
  </code></pre>
  
  <p>Example curl which I'm using:</p>
  
  <pre><code>curl -XPUT elasticUrl/nameOfIndex -d '{
     "settings": {
        "number_of_shards": 1
     },
     "mappings": {
        "title": {
           "properties": {
              "text_field": {
                 "type": "string",
                 "term_vector": "yes"
              }
           }
        }
     }
  }'
  </code></pre>