Turkish localization

[ekinakyurek]

I couldn't make Turkish localization work. Could you help me ?

julia> using StrICU
julia> set_locale!("tr_TR")
julia> StrICU.tolower("AI") #"aı"
ERROR: failed to map case
Stacktrace:
 [1] error(::String) at ./error.jl:33
 [2] tolower(::String) at /Users/ekin/.julia/packages/StrICU/7xZCC/src/ucasemap.jl:40
 [3] top-level scope at none:0

[ScottPJones]

I'll need to add tests for using String type.
The ICU library uses UTF-16, so you should also be using the Strs.jl package, with the UTF16Str type.
That will work correctly (and be faster for many things than using String).

julia> typeof(s)
UTF16Str

julia> StrICU.tolower(s)
"aı"