msvcrt: Add implementation of _strncoll

[Piotr Caban]

On 11/15/10 14:53, Vitaly Perov wrote:
>> This function should be implemented without memory allocations.
> Why? I don't think it is possible to implement it without any memory
> allocations.
I mean without copying the strings.

Using strcoll doesn't make much sense (here and in MSVCRT_strcoll 
implementation). If a broken/partial implementation is needed by an 
application using strncmp should be ok.