Added text input types function

As per the request https://github.com/zurb/foundation/issues/5712

Accepts a custom selector, which defaults to 'input'. Can also accept a list of types if having all types is overkill.

Example:

```scss
#{text-inputs( email url textarea, '.form-control')} {
    border-color: $oil;
    &:focus {
      border-color: $primary-color;
    }
}
```