Remove the locale abbreviation hacks

[johnbillion]

WP_Locale uses two nasty hacks for weekday initials and month abbreviations which involve appending a string to the abbreviations in order to make them unique.

These were introduced in [1518] and [2232] to fix #10 and #722 respectively.

I think it's time we switched to the dedicated _x() function, which is intended for this purpose. Is there any reason not to do this?

@ocean90 Is this something we can update in the existing translations database to avoid the need for re-translation?

[ocean90]

Looks good, and yes, we can use existing translations for this.

[SergeyBiryukov]

In 34046:

Use _x() instead of string hacks for weekday and month abbreviations.

Props johnbillion.
Fixes #33716.

[pavelevap]

+1

Is there any reason why using _x()? This function was designed for different usage of the same string? Translators comment should be enough?

[SergeyBiryukov]

Replying to pavelevap:

Is there any reason why using _x()? This function was designed for different usage of the same string? Translators comment should be enough?

'S' is ambiguous, it means both Saturday and Sunday. Same for 'T' (Tuesday and Thursday).

'May' is also ambiguous, it's used for both the full month name and the abbreviation, which may differ in some languages.

Others just use _x() for consistency.

[pavelevap]

Thank you, Sergey! I did not notice that, we have unique first letters for all days :-)

[pavelevap]

@SergeyBiryukov: Maybe we should also change translator comments? For our language is better two-letter abbreviation of each day, but translator comment suggests that we should use one-letter initial (and same for months).