[locale/ar] Use native plural forms

[forabi]

No description provided.

[forabi]

Closes #1799

[butterflyhug]

Awesome! Looks like you'll need to update the tests to expect the right plural forms, though.

[Menelion]

@forabi, yes, please change the tests accordingly.

[forabi]

@Oire I updated the tests

[ichernev]

@abdelsaid can you please verify this change

[forabi]

Looks like he deleted his account. I understand you need some form of verification, but the old translations are the incorrect ones, they were simply a 1:1 translation of the English strings, many translators do not care enough to use the correct forms because either they do not know how to implement the correct forms or the code does not provide a way to implement them and they need to rewrite core functions to handle this case, which may not be easy.

[ichernev]

This looks good then. Will merge in next patch release.

[ichernev]

Merged in 25df5b3