Enforce line breaks in between types and variables, functions, or classes

These should produce violations:

``` typescript
type X = "string";
const foo = "bar";
```

``` typescript
type X = "string";
const foo = () => {
// do whatever
}
```

``` typescript
type X = "string";
function foo() {
// do whatever
}
```

``` typescript
type X = "string";
class A {
// ...
}
```

No source file or test is named in the issue. Start by locating the configuration or rule responsible for spacing between declarations, then verify the four TypeScript examples and ensure each missing line break produces a violation.

Written by the indexing model from the issue text.