Upgraded to Laravel 5.6.

Author: dmitry-ivanov

README.md

@@ -18,6 +18,7 @@ Provides Laravel-specific and pure PHP helper functions.
 | 5.3.*   | [5.3.*](https://github.com/dmitry-ivanov/laravel-helper-functions/tree/5.3) |
 | 5.4.*   | [5.4.*](https://github.com/dmitry-ivanov/laravel-helper-functions/tree/5.4) |
 | 5.5.*   | [5.5.*](https://github.com/dmitry-ivanov/laravel-helper-functions/tree/5.5) |
+| 5.6.*   | [5.6.*](https://github.com/dmitry-ivanov/laravel-helper-functions/tree/5.6) |
 
 ## Usage