Zabbix

..F....... [DEV-3870] added global constant for "_csrf_token" in Javascript

* commit '5ffebced936809ec2d17ee35064d701071cd51e5':
  ..F....... [DEV-3870] improved code style
  ..F....... [DEV-3870] returned class constant to maintain backward compatibilty of modules
  ..F....... [DEV-3870] fixed typo
  ..F....... [DEV-3870] added global constant for "_csrf_token" in Javascript

(cherry picked from commit 18c130785aee664d863c43a2613912844bc01bb9)