[PATCH] Date#to_s should use I18n

Could you submit a patch ?

I worked a bit on this problem and attached a patch. Two tests are not passing because I wanted to hear your opinion on the desired behavior. It does only apply to master and would need to be ported to 2-3stable manually.

I added I18n to Time, Date, Datetime and TimeWithZone. There is a test for each of the following cases:

• to_s with default format
• to_s with undefined format
• to_s with custom format
• to_s with a lambda as custom format

Things I think are worth pointing out:

• The DATE_FORMATS now only includes System-like formats, that don't need to be localized (eg. :db, :number, :rfc822)
• New formats can now be added without extending DATE_FORMATS. The symbol passed to to_s only needs a matching translation.
• If the user passes a lambda as custom format, he has to care about I18n by himself.
• The long_ordinal format is thus not localized (the method ordinalize isn't localized yet either). This problem does not apply to all languages anyway.
• Some formats defined in DATE_FORMATS did not match the formats defined in the locales/en.yml, so I changed some default values in the locale file to satisfy the tests.

And here are the points that are still open and I need your help:

1. /test/core_ext/time_ext_test.rb:496:in test_to_s' fails. I'm not sure if it's just a problem with the assertion or if I messed up something with the timezones.<br/>
2. test/core_ext/date_time_ext_test.rb:14:in test_to_s' fails because the new default value from the locales file does not match the default value previously defined in DATE_FORMATS. I'm not sure what consequences there could be if I just changed the default value.

Please review this patch carefully. It is my first one and I initially felt like it was no big deal but I ended up changing some essential behavior. Plus I'm not really experienced with time zones.

Thanks for your feedback.

This issue has been automatically marked as stale because it has not been commented on for at least three months.

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