Autocomplete: Prefer matches with the same capitalisation

## Suggestion When there are autocomplete matches with the same or similar name but different capitalisation, the matching capitalisation should be preferred. Or the match should be at least consistent - currently, there is no clear behavior. ## Examples How it looks when it doesn't work:  How it looks when it works:  ## Checklist My suggestion meets these guidelines: * [x] This wouldn't be a breaking change in existing TypeScript/JavaScript code * [x] This wouldn't change the runtime behavior of existing JavaScript code * [x] This could be implemented without emitting different JS based on the types of the expressions * [x] This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.) * [x] This feature would agree with the rest of [TypeScript's Design Goals](https://github.com/Microsoft/TypeScript/wiki/TypeScript-Design-Goals).