Deprecated selector in `reggae-syntax/index.less`

In `reggae-syntax/index.less`:

Starting from Atom v1.13.0, the contents of `atom-text-editor` elements are no longer encapsulated within a shadow DOM boundary. This means you should stop using `:host` and `::shadow` pseudo-selectors, and prepend all your syntax selectors with `syntax--`. To prevent breakage with existing style sheets, Atom will automatically upgrade the following selectors:

* `atom-text-editor .search-results .marker .region` => `atom-text-editor .search-results .syntax--marker .region`

* `atom-text-editor .search-results .marker.current-result .region` => `atom-text-editor .search-results .syntax--marker.current-result .region`

* `.brace.square` => `.syntax--brace.syntax--square`

Automatic translation of selectors will be removed in a few release cycles to minimize startup time. Please, make sure to upgrade the above selectors as soon as possible.