Patch for * share command options

[Simo Sorce]

Hello,
I've put up this patch to overcome the fact that current code do not let
you create a share from srvmgr.exe if the unix path does not exist.

I find this behaviour make the functionality nearly unusable, so patched
the code to let the script decide by itslef what to do.
Also tryed to address possible errors but not arguing too much.

If it seem ok I'm going to commit it in HEAD and 3.0

Simo.

P.S: This behaviour matches the one present in lanman.c api_RNetShareAdd
function, a it doesn't check the code if I've read it correctly, so this
patch also make RAP and RPC consistent regarding this functionality

-- 
Simo Sorce - simo.sorce at xsec.it
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