Support passing matcher to filter definition

For some filters, we may want to provide a different matching experience by default. So that e.g. a className filter by default would match if one of the classes matches the given value. It would be cool if we could provide a matcher to use for this.

Note that with the current implementation, a Matcher is an already constructed value with a given value, so what we'd need is something like this:

type MatcherConstructor<T> = (value: T) => Matcher<T>;

Then:

createInteractor('element')
  .filters({
    className: {
      apply: (element) => elemnent.className,
      matcher: (value) => containsWord(value)
    }
  })

Start at the createInteractor filter-definition entry point and read the existing Matcher behavior. Trace how filter values are matched, then support a matcher constructor such as the proposed MatcherConstructor and verify that a className filter can use containsWord-style matching.