Make fuzzy search ignore case by default

### Proposed solution

`string_match` method for `FuzzyQuery` should ignore case by making both pattern and value being matched against lowercase.

### Objective

#### Goals

Make fuzzy searching... *fuzzier*. I don't see a scenario where one would want a fuzzy search but care about capitalization.

Alternative would be to make this behavior toggleable in the config or to have a different prefix for case sensitive vs case-insensitive fuzzy matching.

#### Non-goals

N/A

#### Anti-goals

This could result in unexpected behavior if a user depends on capitalization during fuzzy searching, but I don't see why one would.