Suspicious characters in key: "name:zh-Hans" and "name:zh-Hant" — should be accepted and a description added

[Lepus]

If there is a key name:zh-Hans or name:zh-Hant when pasting the tag, it will prompt "Suspicious characters in key:". However, both are legal BCP-47 language codes. Moreover, the language description can be added in the tag box as "Traditional Chinese" for zh-Hant, and "Simplified Chinese" for zh-Hans.

[Lepus]

In addition, the key of Hanyu Pinyin can be changed from the non-standard name:zh_pinyin to the BCP-47 standard name:zh-Latn-pinyin.

[stoecker]

In 19042/josm:

fix #23625 - allow - sign in keys