title: Elasticsearch 'failed to find filter under name '
body: <p>I'am just started with ES 5.2.2
  Trying ad analyzer with support russian morhology.
  Run ES using docker, i create image with installed elasticsearch-analysis-morphology.
  then i:
  Create index, 
  then put settings</p>
  
  <p>after that get settings, and all sems right</p>
  
  <pre><code>curl http://localhost:9200/news/_settings?pretty
  {
  "news" : {
  "settings" : {
    "index" : {
      "number_of_shards" : "5",
      "provided_name" : "news",
      "creation_date" : "1489343955314",
      "analysis" : {
        "analyzer" : {
          "russian_analyzer" : {
            "filter" : [
              "stop",
              "custom_stop",
              "russian_stop",
              "custom_word_delimiter",
              "lowercase",
              "russian_morphology",
              "english_morphology"
            ],
            "char_filter" : [
              "html_strip",
              "ru"
            ],
            "type" : "custom",
            "tokenizer" : "standard"
          }
        },
        "char_filter" : {
          "ru" : {
            "type" : "mapping",
            "mappings" : [
              "Ё=&gt;Е",
              "ё=&gt;е"
            ]
          }
        },
        "filter:" : {
          "custom_stop" : {
            "type" : "stop",
            "stopwords" : [
              "n",
              "r"
            ]
          },
          "russian_stop" : {
            "ignore_case" : "true",
            "type" : "stop",
            "stopwords" : [
              "а",
              "без",
            ]
          },
          "custom_word_delimiter" : {
            "split_on_numerics" : "false",
            "generate_word_parts" : "false",
            "preserve_original" : "true",
            "catenate_words" : "true",
            "generate_number_parts" : "true",
            "catenate_all" : "true",
            "split_on_case_change" : "false",
            "type" : "word_delimiter",
            "catenate_numbers" : "false"
          }
        }
      },
      "number_of_replicas" : "1",
      "uuid" : "IUkHHwWrStqDMG6fYOqyqQ",
      "version" : {
        "created" : "5020299"
      }
    }
   }
  }
  }
  </code></pre>
  
  <p>then i try open index but ES give me this:</p>
  
  <pre><code>{
  "error" : {
  "root_cause" : [
    {
      "type" : "exception",
      "reason" : "Failed to verify index [news/IUkHHwWrStqDMG6fYOqyqQ]"
    }
  ],
  "type" : "exception",
  "reason" : "Failed to verify index [news/IUkHHwWrStqDMG6fYOqyqQ]",
  "caused_by" : {
    "type" : "illegal_argument_exception",
    "reason" : "Custom Analyzer [russian_analyzer] failed to find filter         under name [custom_stop]"
  }
  },
  "status" : 500
  }
  </code></pre>
  
  <p>Can't understand where i'm wrong. 
  Can anyone see what the problem is?</p>