replace UTF32String usage for Julia 0.3 & type-stability

[stevengj]

The UTF32String constructor semantics are likely to change in Julia 0.3 (and this identifier was not defined in Julia 0.2); see JuliaLang/julia#7016

However, there is an easy fix (compatible with Julia 0.2) which has the added benefit of making your makeidentifier function type-stable. Just replace

cs = UTF32String(res)

with cs = utf8(res).

This will give you type stability, since you subsequently return in(cs, RESERVED_WORDS) ? "_"*cs : cs, and "_"*cs gives a bytestring even if cs is a UTF32String. If cs is a UTF8String, this will always return a UTF8String.

[johnmyleswhite]

Closed by 7ee7651