Patch to add support for advertising FULLSYNC to Mac OSX Clients

[Kevin Anderson]

Hi Jeremy,
   I would appreciate it if someone could reach out to Apple regarding
the detail of the specification since I do not have any contacts there
myself.


> Blocking is not a magic bullet. It doesn't get you
> anything waiting for an async response doesn't also
> get you.


This is my first attempt at getting something to work within the SMB
protocol so for my own information, to make this flush request
asynchronous would you pend the SMB Flush Response back to the client
till an fsync is completed by the server? Or does the current code
already have that same effect?