[NTDLL]

[NTDLL]
Export RtlMapSecurityErrorToNtStatus since we have it available in our RTL library (however it is still only stubbed).

[RTL][NDK]
- NT-ify a bit error.c
- Add the prototypes of the functions that manipulate the "last Win32 error" and "last NT status".
- Add the prototypes of the functions that get & set the thread-error-mode (for hard-errors).
- Define some prototypes for NTOS_MODE_USER only.

[CONSRV]
RtlGetLastNtStatus is now in the NDK, no need to keep its prototype there anymore.

svn path=/trunk/; revision=71767