Not possible to specify mappings for an attachment's title

[joshclark]

When creating an attachment field, I'd like to be able to specify mapping settings for the attachment's title. I can do this for the file, author and date (see AttachmentMappingDescriptor) but I can't do this for the title or keywords. See http://www.elasticsearch.org/guide/reference/mapping/attachment-type/ for a description of these fields. It looks like we just need to add a TitleField and a KeywordsField method to AttachmentMappingDescriptor just like has been done for the AuthorField.

The mapping I'm trying to get looks something like this:

  "contents": {
    "type": "attachment",
    "fields": {
      "contents": {
        "type": "string",
        "store": "yes",
        "term_vector": "with_positions_offsets"
      },
      "author": {
        "type": "string",
        "store": "yes"
      },
      "title": {
        "type": "string",
        "store": "yes"
      },
      "date": {
        "type": "date",
        "store": "yes"
      }
    }

[Mpdreamz]

Thanks added them and also Metadatafield(string name, func mapping) to specify any field. See the updated tests.