[NTOSKRNL]

[NTOSKRNL]
- Implement SepAdjustPrivileges, which does both the counting of (changed) privileges as well as applying them, when requested. Use it in NtAdjustPrivilegesToken twice instead of duplicating the code there.
- Fix return value of NtAdjustPrivilegesToken by making sure to properly count the found privileges and check against the provided ones
- Lock the Token, while messing with the privileges
- Add support for SE_PRIVILEGE_REMOVED
- Proplery (re)calculate Token flags after changing privileges
- Improve failure pathes by using a common cleanup label
- Don't free the allocations atatched to the token in SepCreateToken on failure, since ObDereferenceObject will already do that.
- Make priviliges constants instead of initializing them.

svn path=/trunk/; revision=61109