Add missing time zone definitions for Russian Federation

[Envek]

Today I've noticed that Rails' time zone mapping is missing next russian time zones completely:

• UTC+02 Kaliningrad
• UTC+04 Samara
• UTC+11 Srednekolymsk

Also I noticed that currently mapping points Volgograd to Europe/Moscow but in zones.tab from current tzdata (2014j) there is explicit Europe/Volgograd timezone exists. Changed it.

And last thing: I added mapping for all russian timezones from tzdata (such that Simferopol, Novokuznetsk, and Chita), but all of them duplicates main timezones (Moscow, Novosibirsk, and Irkutsk respectively), and these entries in zones.tab looks actual. Please tell me should I include such entries in this PR or not.

For more info see file zones.tab from tzdata, rows 329 to 349 and Wikipedia article about time in Russia. Please note that there were two large time zone changes in last years in Russia.

[rafaelfranca]

cc @pixeltrix

[pixeltrix]

@Envek the mappings list is not meant to be an exhaustive list but I'm happy for the correction to Volgograd to be merged. The list is for broad worldwide audience but if you need all possible timezones I suggest rolling your own UX because present a massive drop drown isn't a great experience.

[Envek]

OK, removed entries that duplicated existing ones with same UTC offset.

But I think entries for Kaliningrad, Samara and Srednekolymsk should be added as there is currently no russian time zones with that offsets are present in mapping.

So, with this PR merged, list of russian time zones will be as follows:

(GMT+02:00) Kaliningrad (NEW)
(GMT+03:00) Moscow
(GMT+03:00) St. Petersburg
(GMT+03:00) Volgograd (CHANGED)
(GMT+04:00) Samara (NEW)
(GMT+05:00) Ekaterinburg
(GMT+06:00) Novosibirsk
(GMT+07:00) Krasnoyarsk
(GMT+08:00) Irkutsk
(GMT+09:00) Yakutsk
(GMT+10:00) Magadan
(GMT+10:00) Vladivostok
(GMT+11:00) Srednekolymsk (NEW)
(GMT+12:00) Kamchatka

For better UX I already created initializer like that: https://gist.github.com/Envek/cda8a367764dc2cacbc0

[pixeltrix]

Okay, I can understand that - thanks for the PR 👍

[Envek]

Thanks for review! Can it be also backported to 4.2?

[pixeltrix]

Backported to 4.2 (12a40a8) and 4.1 (b25efc0)