Add mapping for metadata filter name config.

[anlowee]

For now, the metadata filter name does not support mapping:

"columnName": "author"

We want something like:

"columnName": "author*"

which can map all columns start with author.

[kirkrodrigues]

Can you provide more detail? I assume you're talking about mapping a data column name to a metadata column name. But in that case, how can a data column name map to a wildcard metadata column name?

[anlowee]

This is from Ray's comment in #19. Essentially he means that provide a feature that adding all columns matching a pattern as filters. For example, say there is a filter:

{
  "columnName": "author*",
  "required": true
}

Then all columns start with "author" should be pushed down and exist in the generated metadata filter query.