Extend NTIMES to allow setting create_time

Extend NTIMES to allow setting create_time

1) Add in smb_file_time struct to clarify code and make room for createtime.
2) Get and set create time from SMB messages.
3) Fixup existing VFS modules + examples Some OS'es allow for the
setting of the birthtime through kernel interfaces. This value is
generically used for Windows createtime, but is not settable in the
code today.