converted smbd to use NTSTATUS by default

major changes include:

- added NSTATUS type
- added automatic mapping between dos and nt error codes
- changed all ERROR() calls to ERROR_DOS() and many to ERROR_NT()
  these calls auto-translate to the client error code system
- got rid of the cached error code and the writebmpx code

We eventually will need to also:
- get rid of BOOL, so we don't lose error info
- replace all ERROR_DOS() calls with ERROR_NT() calls

but that is too much for one night
(This used to be commit 83d9896c1e)

source3/libsmb/libsmbclient.c

@@ -1650,7 +1650,7 @@ int smbc_opendir(const char *fname)
 	    free(smbc_file_table[slot]);
 	  }
 	  smbc_file_table[slot] = NULL;
-	  errno = cli_error(&srv->cli);
+	  errno = cli_errno(&srv->cli);
 	  return -1;
 
 	}