toProperCase with UTF Characters

[Demonslay335]

I have had a few users note that their language's text is improperly capitalized. I have traced this down to the toProperCase() function. It ends up capitalizing the first Latin character, making some texts look funny. This is easily reproducible even with the demo. An example language is Czech (becomes "čEština" instead of "Čeština").

I believe the issue is with the regex replace() part. The closure part works fine if isolated, since toUpperCase() works on UTF-8 natively.

return a.charAt(0).toUpperCase()+a.substr(1).toLowerCase()