[member-ordering] feature request: differentiate methods and callback signatures

[tao-cumplido]

• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I have read the FAQ and my problem is not listed.

Repro

{
  "rules": {
    "@typescript-eslint/member-ordering": ["error"]
  }
}

interface X {
  (): void;
  a:  unknown;
  b(): void;
}

Expected Result

Have an option to differentiate callback signatures from methods for ordering, similar to the signature and *-field options

Actual Result

3:3 - Member a should be declared before all method definitions.(@typescript-eslint/member-ordering)

Additional Info

Versions

package	version
@typescript-eslint/eslint-plugin	4.15.0
@typescript-eslint/parser	4.15.0
TypeScript	4.1.5
ESLint	7.19.0
node	14.15.5

[tanohzana]

I can work on this. I'll need about 2 weeks 🙂