CESNET/perun — pull request #78 by jirmauritz (2013-12-19 21:01:35+00:00)
Title: Core: New type of user attribute timezone.

User attribute timezone is now in standart of tz database, http://en.wikipedia.org/wiki/List_of_IANA_time_zones.
- the timezones in string are typed in the module and added to HashSet,
since HashSet has constant time complexity of searching
- timzone attribute modul edited, so as it checks the value according to
the timezones in set
- tests modified