Indices stats options

This PR fixes two bugs in indices stats:

*  `groups` and `types` were being ignored
* `completion_fields` with wildcards were not resolving the real field names

It also allows `groups` and `types` to accept wildcards, like `fields`, `completion_fields` and `fielddata_fields`

Added YAML tests for indices stats for: indices, metrics, level, fields, types, groups
`refresh()`