Replace deprecated usage of ${} for string interpolation (#1032)

Credit to @josephcrowell

Replace deprecated usage of ${} for string interpolation (#1032)

Credit to @josephcrowell

Translations for Turkish language (#1013)

Make cms.beforeRoute a halting event

This change allows developers to prevent the CMS route from being registered.

An example use case for this is loading the CMS content under a set path prefix by re-registering the CMS route with the appropriate prefix in place. Preventing the registration of the default CMS route is required in order to override the mapping of the controller action to URL (and thus have the Cms::url() helper generate the correct URLs in this example). 

Example:
```php
Route::any('docs/{slug?}', 'Cms\Classes\CmsController@run')->where('slug', '(.*)?')->middleware('web');

Event::listen('cms.beforeRoute', function () {
    $path = Request::path();
    // Disable the CMS routes so that the docs/ route can take over for URL generation
    if (Str::startsWith($path, 'docs')) {
        return false;
    }
});
```

Improve type hints

Add licenses

Fix issues with accessing the expected context variables inside of Tw…

…ig macros.

This fixes #578 by adding the ability to pass the CMS Controller instance to the CMS Twig Extension removing the reliance on context variables as well as making the expected "global" twig variables inside of the CMS Twig environment actually global within that environment.

Replaces #598 & #593.

Credit to @RomainMazB for the initial implementation.

Outputs time respecting backend preferences (#572)

Replaces october/*

Merge pull request #401 from wintercms/wip/snowboard

[1.1.8] Implement an opt-in improved JS framework (Snowboard). Documented by wintercms/docs#45