Unreliable loading for zh lang

[yfdyh000]

There are some complex changes in translation loading.
According to user report and tests, the latest version (4.3.1) of this tool is likely to give an error or fail for Chinese users. Like:

• Uncaught TypeError: users.indexOf is not a function
• ⧼not-on-list⧽
• Uncaught TypeError: Cannot set properties of undefined (setting 'zh_hans')

At least the if (JWB.allowed === true && JWB.messages.length == langs + 1) { // if there are two languages to load, wait for them both be suspicious, the zh-cn locale will got "zh-hans"*2 in langs and about five groups in JWB.messages.