Deprecate and remove i18n tools

[ocean90]

The internationalization tools (also known as makepot.php) were added in [25003].
makepot.php was primarily used for generating POT files on WordPress.org servers for core. Later also for bbPress/BuddyPress and WordPress.org projects like Rosetta or the support forums until it was opened for plugins and themes. The canonical source of the tools is still ​https://i18n.trac.wordpress.org/browser/tools/trunk which was causing for files not being in sync in the past.

It has been a great pleasure to work with makepot.php over the past ​11 years but now it's time to say goodbye as there's now a proper replacement for it: ​wp i18n make-pot. 🎉

The new CLI command was ​introduced in WP-CLI 2.0 and provides full parity with makepot.php. Actually even more like auditing strings, parsing strings only of a specific text domain, extracting JavaScript strings and extracting ​PHP strings which weren't caught by makepot.php. Since last week, the build tools on WordPress.org are using the command for string extraction, see ​#meta3748.

Therefore I'm proposing to remove the tools from core.svn and promote the use of wp i18n make-pot and ​concentrate our efforts on the new command.

Tickets which can be closed:

• #37605
• #42747
• #42818
• #43864

[nbachiyski]

❤️ So much progress since the times when “parsing” PHP using a list of tokens was so much fun :)

[swissspidy]

What's needed here to make this happen?

[ocean90]

In 45686:

Tools: Remove internationalization tools (also known as makepot.php).

It has been a great pleasure to work with makepot.php over the past ​11 years but now it's time to say goodbye.
The tools have been integrated into WP-CLI as ​wp i18n make-pot and ​wp i18n make-json. The new commands were optimized to support current PHP versions and are more flexible and reliable when extracting strings for PHP, and JavaScript.

Access to the old tools continue to exist in previous branches or at ​https://i18n.svn.wordpress.org/tools/.

Fixes #45287.