Support for FastGettext 2.0 (bsc#1121865)

[lslezak]

Summary

• Support for FastGettext 2.0 (bsc#1121865)
• Backward compatible with FastGettext 1.6 (present in SLE15/Leap 15.0)
• Tested manually, added an integration test (see below)
• No version upgrade, this will be released with the next maintenance update
• Added rubygem-fast_gettext < 3.0 dependencies to avoid similar issue in the future

Testing

Manual Tests

Simple testing script which prints the FastGettext version and prints a translated string from YaST.

```ruby require "yast" include Yast::I18n puts "FastGettext version: #{FastGettext::VERSION}" textdomain "base" msg = "Updating system configuration..." puts "Message: #{msg}" puts "Translation: #{_(msg)}" ```

When running the script with the original Leap 15.0 package it prints this (in the Czech locale):

FastGettext version: 1.6.0
Message:     Updating system configuration...
Translation: Probíhá aktualizace konfigurace systému...

After updating the package to version 2.0 from the devel:languages:ruby:extensions it prints this:

FastGettext version: 2.0.0
Message:     Updating system configuration...
Translation: Probíhá aktualizace konfigurace systému...

So it works correctly with both FastGettext versions.

Integration Tests

We already have some unit tests for translation in tests/i18n_spec.rb, but these tests basically mock everything so they do not test that the translation process really work.

Therefore I have added a an integration test with some real translations (provided in the attached po/mo files).

[lslezak]

This is for SLE15-GA, we agreed to release it with the next real fix as we do not expect that SLE15/Leap15.0 used would use some external newer gems.

For TW (master) I'll release a new version.

[archon810]

Sorry, how can I get this fix on OpenSUSE 15.0? zypper update shows no updates currently, and yast is still failing like here https://bugzilla.opensuse.org/show_bug.cgi?id=1121865.

Thanks.