Can std.json handle Unicode?

[Jacob Carlborg]

I'm wondering because I see that std.json uses isControl, isDigit and 
isHexDigit from std.ascii and not std.uni. This also causes a problem 
with a pull request I recently made for std.net.isemail. In one of its 
unit tests the DEL character (127) is used. According to 
std.ascii.isControl this is a control character, but not according to 
std.uni.isControl. This will cause the test suite for the pull request 
not to be run since std.json chokes on the DEL character.

https://github.com/D-Programming-Language/phobos/pull/1217
--
/Jacob Carlborg