C++: Introduce unicode char/strings support

Those are the types char16_t and char32_t along with the new
char/string literals u'', U'', u"", u8"", and U"".

This is particularly important for the use of QStringLiteral
since in some platforms it relies on expansion such as above.

Note: The string literals quickfixes still need some tunning.

Task-number: QTCREATORBUG-7449
Change-Id: Iebcfea15677dc8e0ebb6143def89a5477e1be7d4
Reviewed-by: hjk <qthjk@ovi.com>

src/plugins/cpptools/cppcodeformatter.cpp

@@ -851,6 +851,8 @@ bool CodeFormatter::tryDeclaration()
         }
         // fallthrough
     case T_CHAR:
+    case T_CHAR16_T:
+    case T_CHAR32_T:
     case T_WCHAR_T:
     case T_BOOL:
     case T_SHORT: