Change English name for zh and zh-TW to "Chinese/Simplified" and "Chinese/Traditional"
Currently, the English name for two Chinese languages, zh and zh-TW are "Simplified Chinese" and "Traditional Chinese". I suggest changing those to "Chinese/Simplified" and "Chinese/Traditional" for the following reasons.
- I think users look for "C" in the language list box when they want to switch to either of two Chinese languages, but actually they have to look for "S" or "T"
- The two Chinese languages should be displayed side by side
- The style of language name is "language/dialect" in Redmine. For example, "Spanish/Panama" and "Portuguese/Brazil"