[NTFS] - Add a few fixes and improvements, most from CR-123:

[NTFS] - Add a few fixes and improvements, most from CR-123:
-Add ATTR_RECORD_ALIGNMENT define to replace magic value of 8 when we need to adjust an attribute's beginning or length.
-Don't use int's.
-GetPackedByteCount() - Remove unused "bytes" variable.

svn path=/branches/GSoC_2016/NTFS/; revision=75288