1.6.6
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  [+] add captcha image to pre-chat survey
  [+] improve localization (add new constants)
  [!] completely abandon old application name (i.e. webim)
  [!] switch to more safe hashing alrgorithms for passwords and tokens
  [!] switch to more safe generation of user IDs
  [!] make important cookies more safe
  [!] multiple XSS fixes
  [!] multiple SQL Injection fixes
  [!] multiple file path manipulation fixes
  [!] CSRF fixes